Furious Iranians petrol bomb Saudi embassy in Tehran as global protests and fears of sectarian violence escalate over kingdom's mass execution of 47 prisoners including top Shiite cleric 

A furious mob of Iranian protesters petrol bombed Saudi Arabia's embassy in Tehran late last night after the kingdom executed 47 prisoners, including a top Shiite cleric, prompting fears of sectarian violence and further instability in the Middle East.

Enraged demonstrators stormed and set fire to the embassy after Saudi Arabia - which has a seat on the United Nations Human Rights Council - caused outrage around the world with the execution of Sheikh Nimr al-Nimr.

The Iranian Revolutionary Guard promised 'harsh revenge' against the Saudis and former Iraqi Prime Minister Nouri Al-Maliki warned that the executions would 'topple the Saudi regime'. Shiite leaders in Iran, Iraq and Lebanon fiercely condemned the killings.

Meanwhile US and European officials criticized Saudi Arabia for the executions which risk 'exacerbating sectarian tensions', while UN Secretary-General Ban Ki-moon said he was 'deeply dismayed'.

al-Nimr was a driving force behind the protests that broke out in 2011 in the east of Sunni-ruled Saudi Arabia, where the Shiite minority complains of marginalisation. He was condemned as a terrorist by Saudi Arabia and executed alongside 46 other people convicted of 'terrorism' yesterday.

None of the Saudi embassy staff were inside the building in Tehran as protesters broke in and trashed the offices. Photographs showed demonstrators damaging embassy property, including removing the national flag from the building. Iranian police have arrested a number of demonstrators.

Widespread demonstrations erupted in support for al-Nimr, with Shia Muslims from London to India condemning Saudi Arabia for executing the cleric.

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Firefighters arrive at the scene of the Saudi Arabian embassy which was torched by members of an angry mob in Tehran

Iranian protesters set fire to pictures of the Saudi royal family in front of the Saudi Arabian embassy in Tehran

Protesters set about damaging and stealing property from inside the Saudi embassy in the Iranian capital city of Tehran

None of the Saudi embassy staff were inside the building as protesters broke into the building and took out their anger on the offices. Photos have been emerging on social media showing demonstrators damaging embassy property, including removing the national flag from the building

The Saudi Arabian embassy was set alight by members of the crowd, who threw petrol bombs into the building

Hundreds of Shi'ite Muslims marched through the Qatif district of Saudi Arabia's Eastern Province in protest, which was closely watched by security forces with tensions also mounting on the streets of neighbouring Bahrain.

The Qatif protesters chanted 'down with the Al Saud', the name of the ruling Saudi royal family, leading authorities to call in dozens of Saudi military reinforcements. Images have emerged on social media of a bus burning, reportedly in Qatif, as the protests escalated last night.

Protesters in Bahrain were met with tear gas as they clashed with security forces in the suburbs while hundreds demonstrated in Iraq's Shiite holy city of Karbala.

The was widespread condemnation of the executions, with the U.S. State Department saying they 'risk exacerbating sectarian tensions at a time when they urgently need to be reduced'. The statement was echoed almost word for word by a EU foreign policy chief Federica Mogherini.

United Nations Secretary-General Ban Ki-moon said he was 'deeply dismayed' by the execution of al-Nimr.

'Sheik al-Nimr and a number of the other prisoners executed had been convicted following trials that raised serious concerns over the nature of the charges and the fairness of the process,' Ban's spokesman said.

'The Secretary-General also calls for calm and restraint in reaction to the execution of Sheikh Nimr and urges all regional leaders to work to avoid the exacerbation of sectarian tensions.'  

In London, dozens of protesters gathered outside the Saudi embassy to express their anger about the executions.

Amnesty International UK's Shane Enright said the death penalty was 'unacceptable in all circumstances' and it was particularly concerning that a number of 'peaceful dissidents' had been killed, including sheikh al-Nimr.

Speaking at the scene of the demonstration, he said a recent Amnesty report concluded that the trial against him was 'deeply flawed', adding: 'We also came to the conclusion that he was jailed solely for expressing his peaceful points of view, protesting peacefully against the regimes.

'This is an absolute, fundamental, breach of basic human rights,' Mr Enright said.

Despite supporting the capital punishment, Saudi Arabia is a member of the UN Human Rights Council. Secret diplomatic cables exposed in September last year appeared to show that the UK helped the kingdom join in a vote-trading deal.

al-Nimr's execution has sparked fierce criticism from Shiite communities in Iran, Iraq, Lebanon, Yemen and Indian-controlled Kashmir. 

One of the 47 men executed in Saudi Arabia was Adel al-Dhubaiti, the al-Qaeda gunman convicted for the attempted assassination of BBC security correspondent Frank Gardner and the murder of his cameraman Simon Cumbers.

Mr Gardner was shot six times and left paralysed whilst he was filming a report with Simon Cumbers in June 2004. He was offered the chance to meet al-Dhubaiti when he was sentenced in 2014 but declined. 

Flames burn inside the offices of the embassy, where staff had already evacuated from inside the building

Angry crowds in Iran protesting at Saudi Arabia's execution of a top Shiite cleric hurled petrol bombs and stormed the kingdom's embassy in Tehran late tonight before being cleared out by police

Many of the protesters in London gathered in support for Nimr al-Nimr, calling for the action against the Saudi regime

Killed: Shiite Sheikh Nimr al-Nimr, a 56-year-old cleric was a driving force of the protests that broke out in 2011 in Qatif, eastern Saudi Arabia. Above, a Yemeni protests Nimr al-Nimr's death sentence (file photo)

Demonstrators protest outside the Saudi Embassy in London, following Saudi Arabia's execution of 47 prisoners in one day

Enraged Bahraini demonstrators pulled up a palm tree trunk to make a blockade in the street against security forces at a demonstration

One Kashmiri Shiite holds a Hezbollah flag shout slogans against the execution of Sheikh Nimr al-Nimr during a protest in Srinagar

Bahrain security forces have been deployed on the streets in several villages near Manama over fears of demonstrations

Concerns remain that Saudi Arabia's decision to execute 47 prisoners may lead to further sectarian tension in the region

Protesters holding a banner saying 'Death is normal to us and our dignity from God is martyrdom' in Manama, Bahrain

Kashmiri Shiite men and children sit united in front of a candle light vigil in honour of Sheikh Nimr al-Nimr, who was executed in Saudi

Protests: Saudi Arabia's execution of Shiite cleric Nimr al-Nimr has outraged Shia leaders and communities in Iran, Iraq, Lebanon, Yemen and Indian-controlled Kashmir (pictured)

Iran's Shia leadership said the execution of Nimr 'would cost dearly' and an Iranian-backed Shiite militia in Iraq called the execution a 'new crime' carried out by the Saudi royal family.  

Saudi Arabia has said that Iran is responsible for protecting the Kingdom's embassy as the violence grows at the demonstrations.

One Shiite militia in Iraq called on Baghdad to 'reconsider the benefit of having a Saudi embassy in Iraq, with a suspicious ambassador and goals.'

Former Iraqi Prime Minister Nouri Al-Maliki warned in a statement that the execution of the Shiite cleric 'will topple the Saudi regime'. 

But most of the 47 executed in the kingdom's biggest mass execution for decades were Sunnis convicted of al Qaeda attacks in Saudi Arabia a decade ago. Four, including Nimr, were Shi'ites accused of shooting policemen. 

The executions took place in 12 cities in Saudi Arabia, with four prisons using firing squads and the others beheading. 

The United Arab Emirates and Bahrain, members of a Saudi-led coalition battling Iran-backed Shiite rebels in Yemen, praised their ally. 

UAE Foreign Minister Sheikh Abdullah bin Zayed al-Nahyan called the executions a 'clear message against terrorism and those who call for and incite sedition and unrest to tear apart the society's unity and threaten social peace in the kingdom'.

Bahrain, which has itself faced unrest from its Shiite majority population, also backed Riyadh in 'all deterrent and needed measures it takes to confront violence and extremism'.

Protests and large gatherings were held in remembrance for the prominent Shi'a cleric, who was killed alongside 46 other people

The United Arab Emirates and Bahrain, members of a Saudi-led coalition battling Iran-backed Shiite rebels in Yemen, praised their ally, but protests broke out in Bahrain's suburbs

Bahrain has faced unrest from its Shiite majority population, and backed Riyadh in 'all deterrent and needed measures it takes to confront violence and extremism'

Protesters clashed with security forces in a number of villages in Bahrain, where the government has sided with their ally Saudi Arabia

Clash: Protesters clashed with security forces in Bahrain as security forces tried to suppress the angry demonstators

Saudi women hold up posters depicting Shiite Muslim cleric Nimr al-Nimr at a protest in the eastern coastal city of Qatif

In the suburbs of the Bahraini capital Manama however, dozens of Shiite youth gathered for small demonstrations to condemn the executions. Clashes quickly escalated between demonstrators and security forces, who released tear gas to disperse the gathering.

A cleric from Bahrain who was at the protest in Iraq's Karbala, said the world should react to Nimr's execution. 'Sheikh Nimr was an icon for Islamic resistance,' Sheikh Habib al-Jamri told AFP.

'His words were his weapon. They couldn't defeat his words so they detained him, tortured him and today executed him in front the world's eyes, like a challenge to global conscience.' 

Bahrain was one of the countries caught in the centre of the Arab Spring in 2011, with the country's Shiite majority population heavily suppressed during protests against the monarchy. Bahrain has remained a close ally of Saudi, who have been careful to safeguard the country during the Arab Spring. 

Shiite protesters in Bahrain in 2011 called for the constitutional reform of the monarchy before security forces heavy handedly clamped down on demonstrations leading to calls for the end of the monarchy. 

The protests in Bahrain yesterday come after opponents have repeatedly been detained and stripped of their citizenship for speaking out against the Bahraini government and the actions of their ally Saudi Arabia.

Saudi Arabia has executed 47 people convicted of 'terrorism' yesterday, including a prominent Shiite cleric behind anti-government protests

Executed: The ministry statement, carried by the official SPA news agency, said the 47 had been convicted of adopting the radical 'takfiri' ideology, joining 'terrorist organisations' and implementing various 'criminal plots'. Above, Shiite cleric Nimr al-Nimr was one of the 47 people executed yesterday

Al Qaeda in the Arabian Peninsula (AQAP) threatened to retaliate against Saudi Arabia for any execution of its members in December.

The list also includes Fares al-Shuwail who has been described by Saudi media outlets as the top religious leader of Al-Qaeda in Saudi Arabia. He was arrested in August 2004.

The ministry statement said the 47 had been convicted of adopting the radical 'takfiri' ideology, joining 'terrorist organisations' and implementing various 'criminal plots'.

The list also includes Sunnis convicted of involvement in Al-Qaeda attacks that killed Saudis and foreigners in the kingdom in 2003 and 2004.

International rights group Reprieve, who works to abolish the death penalty has condemned Saudi Arabia's execution of 47 people, saying two were teenagers when they were detained.

Reprieve says the 47 people whose execution was announced Saturday include four Shiite dissidents.

It says one of the dissidents, Ali al-Ribh, was 18 when he was arrested in 2012, and another, Mohammed al-Shuyokh, was 19.

Both were convicted on charges related to anti-government protests in eastern Saudi Arabia, where the Shiite minority is centered. 

Repercussions: Iran's Shia leadership said the execution of Nimr 'would cost dearly' and an Iranian-backed Shiite militia in Iraq called the execution, a 'new crime' carried out by the Saudi royal family

Soon after the announcement was made, the country's top cleric Grand Mufti Sheikh Abdulaziz Al Sheikh said that the executions were in line with Islamic law and required to safeguard the kingdom's security. Above, Shia protests in Indian-controlled Kashmir

Mourning: Shiite Sheikh Nimr al-Nimr was a persistent critic of Saudi Arabia's Sunni royal family and a driving force of the protests that broke out in 2011 in the Sunni-ruled kingdom's east, where the Shiite minority complains of marginalisation. Above, men protest his execution in Indian-controlled Kashmir

Ahead of the announcement their mothers wrote a letter of thanks, published in The Independent today, along with the mothers of other youths sentenced to death in Saudi Arabia. 

Reprieve said in a statement that the Saudi government 'is continuing to target those who have called for domestic reform in the kingdom.' 

Quoting the Koran, the Saudi Arabian Interior Ministry statement said: 'The recompense of those who wage war against Allah and His Messenger and do mischief in the land is only that they shall be killed or crucified or their hands and their feet be cut off from opposite sides, or be exiled from the land.' 

While the list does not include Nimr's nephew, Ali al-Nimr, who was 17 when he was arrested following the protests, concerns are growing for his fate.

His sentencing to death by beheading and crucifixion sparked an international outcry. Official charges against Nimr include attending a protest, using his phone to encourage further support for the demonstrations and possessing a gun, an accusation which the family strongly denies.

British shadow foreign secretary Hilary Benn told the Press Association: 'With the carrying out of this large number of executions there will now be huge international concern about what will happen to Ali Mohammed al-Nimr who is Sheikh al-Nimr's nephew.

'The Foreign Secretary has told Parliament that he does not expect Ali Mohammed al-Nimr to be executed but he now needs to seek fresh assurances that he will be reprieved.' 

Protest: Scores of Shi'ite Muslims marched through the Qatif district of Saudi Arabia's Eastern Province in protest at the execution of cleric Nimr al-Nimra (file photo)

Dozens of protesters gathered outside the Saudi embassy in London to express their anger about the executions

Amnesty International UK's Shane Enright was at the protest outside the Saudi Embassy in London (pictured). He said a recent Amnesty report concluded that the trial against Nimr was 'deeply flawed'

Death toll: Executions have increased in the kingdom since King Salman acceded to the throne in January 2015 following the death of king Abdullah (file photo)

The Sheikh's brother Mohammed al-Nimr said that the executions came as a 'big shock' because 'we thought the authorities could adopt a political approach to settle matters without bloodshed.'

'There will be reactions,' he said, but urged people to 'adopt peaceful means when expressing their anger.' 

He says the family has not yet been asked to pick up the body but that a funeral would be held as soon as possible. 

The execution of al-Nimr was expected to escalate tensions in eastern Saudi Arabia, where the Shiite minority is concentrated, and Bahrain, which has seen years of simmering unrest between its Shiite majority and Saudi-allied Sunni monarchy. 

Those executed include an Egyptian and a Chadian. The rest were all Saudis.

Executions have increased in the kingdom since King Salman acceded to the throne in January 2015 following the death of king Abdullah.

The number of convicts executed on Saturday is more than half of those executed under Salman's predecessor in the whole year of 2014, which tallied 87.

In 2015, Saudi Arabia executed 153 people convicted of various crimes, including drug-trafficking.

Authorities in the kingdom set up specialised courts in 2011 to try dozens of Saudis and foreigners accused of belonging to Al-Qaeda or of participating in the wave of attacks that swept the country from 2003, which killed 150 Saudis and foreigners.

The kingdom's current Crown Prince Mohammed bin Nayef oversaw a crackdown on the militants at the time.

But Nimr was arrested for completely different reasons in 2012.

The interior ministry had described him at the time as an 'instigator of sedition' as it announced his arrest in the Shiite village of Awamiya in the east after being wounded in the leg while putting up resistance.