Egypt has pledged to hunt down an armed group that killed 25 policemen in the Sinai desert on Monday in an incident that will fuel fears about the country's already grave political crisis worsening to involve attacks by jihadi-type movements.
Egyptian state TV reports from the scene near the border with Israel and the Palestinian Gaza Strip town of Rafah said the terrorists had forced the police conscripts off two minibuses and executed them in cold blood. Three others were injured. Cairo sources describe the killers as "Takfiris" – a term often used for al-Qaida and like-minded groups.
The policemen were in civilian clothes and had been returning to their base from leave. Their corpses were photographed lined up by the roadside.
A total of 70 troops and police have reportedly died in five days of large-scale bloodshed across Egypt, but this was the largest number of casualties suffered by the security forces in a single incident.
Of around 850 fatalities, the majority appear to have been unarmed supporters of the Muslim Brotherhood and deposed president Mohamed Morsi, including nearly 400 killed – according to new figures – when security forces stormed the Rabaa al-Adawiya protest camp in eastern Cairo last Wednesday.
In a report on Monday, Human Rights Watch called the outcome the "worst unlawful mass killings" in Egypt's modern history and said that the death toll appeared to be at least 377, significantly higher than the latest count of 288 by Egypt's health ministry.
Egypt's interim president, Adli Mansour, and the armed forces chief, General Abdel-Fatah al-Sissi, met to discuss the Sinai incident – the main item on national news broadcasts throughout the day.
State TV said the attack could be retaliation for the arrest of Mohamed al-Zawahiri, brother of the Egyptian-born al-Qaida leader, Ayman al-Zawahiri, who was detained on Sunday. Other Arab media said it could be retaliation for the Rabaa killings.
Sinai is a well-known route for smuggling weapons and drugs as well as a base for cross-border attacks on Israel.
Security analysts have warned that such incidents could escalate if Egypt's wider political crisis is not defused. But all the signs in Cairo now are that the military-backed interim government intends to go ahead with plans to ban the Brotherhood. The risk is that it will be forced underground and that moderate Islamists who had believed that the path to power lay through elections may switch to a strategy of violence – the lesson of Algeria's bloody civil war in the 1990s. Arrests of Brotherhood members continued on Monday.
Although the Brotherhood insists it has no links with jihadi groups, Egyptian government sources and state media are now painting the organisation as a terrorist entity and conflating it with violent Islamist groups. Its supporters have been seen firing weapons when demonstrations are attacked.
Islamists have also been blamed for attacks on police stations and churches, though the Brotherhood itself has denied being responsible.
On Monday the group accused the government of carrying out a new atrocity after 36 prisoners who were detained at a Cairo mosque at the weekend died while being moved to the Abu Zaabal prison near the capital. The Interior Ministry said they had been suffocated by tear gas during an attempted escape on Sunday. But the Committee to Monitor Human Rights Violations told a Cairo press conference on Monday that the authorities had given different and contradictory versions and called for an independent and impartial investigation. Committee activists displayed graphic images – charred and unrecognizable corpses with appalling injures – of the victims of Rabaa and other mass killings, "The murders [of the prisoners] show the violations and abuses that political detainees who oppose the July 3 coup [removing Morsi] get subjected to," the Brotherhood said in a statement. The interim prime minister, Hazem Beblawi, was reported to be seeking to clarify the circumstances of the deaths with the ministers of justice and the interior.
Amnesty International said that even if some of Morsi's supporters had used violence against the security forces as they broke up demonstrations calling for his return to office, "that could never justify such a disproportionate response" from police and troops, its secretary general Salil Shetty said in London. "A clear violation of international law and standards has been carried out in Egypt in what can be described as no less than utter carnage."
The Brotherhood called for nine new protest marches across a calmer Cairo on Monday after a heavy security force presence on Sunday brought a smaller turnout than on previous days. A curfew remains in force from 7pm to 6am under emergency laws re-imposed last week.
Human Rights Watch also said that since Morsi's removal sectarian tensions had been on the rise, with Brotherhood leaders scapegoating Christians. Mobs chanting Islamist slogans had attacked at least 32 churches and burned at least 20 across the country.