Pictured: Two senior British officers killed by roadside bomb while on a secret mission... to gain the trust of local Afghans

Squadron Leader Anthony Downing (left) and Royal Marine Captain Tom Jennings (right) were both died after their vehicle was caught in a blast in Afghanistan

Captain Jenning's body was repatriated today in a C17 plane that landed at RAF Brize Norton

It is the first time two officers have been killed by a booby-trap bomb while travelling together in the same vehicle in the warzone.

Capt Jennings, 29, a commando in the Royal Marines before joining the SBS, died when the armoured vehicle struck an improvised explosive device south of the capital Kabul on December 22.

He was the highest-ranking Marine to die in the ten-year conflict.

Sqn Ldr Downing, 34, survived the initial blast and was airlifted to the Queen Elizabeth Hospital in Birmingham.

But he died from his injuries a day later with his family by his bedside. He was the most senior British airman to die in Afghanistan.

It took the total of UK servicemen and women killed fighting the Taliban to 393.

Their loss was all the more acute because it happened as military families prepared to mark Christmas and the New Year knowing their loved ones were facing mortal danger thousands of miles away.

War zone: The roadside bomb went off just south of Kabul in Afghanistan

The team was on a top secret counter-insurgency mission when they were targeted. They had been in contact with Afghans on an ‘outreach patrol’.

Sqn Ldr Downing acted as an interpreter because he was a trained Dari speaker.  This meant he could hold conversations with local people in a bid to persuade them to support the government.

Precise details of the operation were being kept under wraps by the Ministry of Defence but elite Special Forces troops regularly escort MI6 officers and other intelligence officials for meetings with key sources or Taliban chiefs.

Capt Jennings, who was based at SBS headquarters in Poole, Dorset, leaves behind a wife and two young sons.

The MoD described the commando as ‘a true leader, selfless in his professional approach  serving those who were his responsibility’.

He worked alongside local Afghan security forces with ‘empathy and a broad cultural understanding’.

A statement released by the MoD said: ‘Dedicated and humble, he was an archetypal Royal Marine with a keen sense of humour even when faced with adversity.’

Capt Jennings is the second member of the feared SBS to be killed in action in Afghanistan. Corporal Seth Stephens, 42, was shot dead during a top secret mission in the Taliban stronghold of Haji Wakil in Helmand in July 2010.

He received a posthumous Conspicuous Gallantry Cross for bravery.

Sqn Ldr Downing, from near Deal, Kent, was an engineering officer who deployed to Afghanistan because of his language skills.

He was involved in the planning and conduct of outreach patrols, said the MoD.

He was the last to oversee the safety of the RAF’s Nimrod MR2 spy planes before they were taken out of service last year.

He was also a key member of the Mountain Rescue Team at RAF Kinloss in Scotland and had previously been a volunteer for the Samaritans.

His childhood dream was to join the RAF.

Sqn Ldr Downing leaves his parents Michael and Masheeda, a brother and girlfriend.

His parents said: ‘We treasure the memories and the achievements of his fantastic life and without him our lives have been diminished.’

Sqn Ldr Downing was planning to take part in the gruelling Arch to Arc endurance event in 2013.

Captain Jennings' body was today driven out of the air base in Oxfordshire past a flag that has been lowered to half mast

Squadron Leader Downing died of his wounds last Friday at the Queen Elizabeth Hospital in Birmingham. His family were with him when he died