A video showing an attack by British Muslim Abdul Waheed Majeed on Aleppo prison, is the first known evidence of a suicide bomb attack by a Briton in Syria.
Majeed originally went to Syria to help at a refugee camp on the Syria/Turkey border six months ago, and regularly sent home pictures of his humanitarian work to his family back in the UK.
However about nine days ago, the phone calls and emails stopped coming as Majeed appears to have become radicalised and joined the fight against Syrian President Bashar al-Assad.
The video above from Channel4 News shows Majeed looking stressed and nervous as he prepared with Russian caucasus fighters aligned with Jabhat al-Nusra to drive a heavily armoured dump-truck asked with explosives towards the walls of Aleppo prison to try and break out the rebel fighters held within.
The attack was a failure, with the the explosives going off early, and the leader of a rebel brigade killed in the firefight that ensued.
In the UK, Majeed was previously linked to the banned extremist al-Muhajiroun group in the UK that was behind the failed fertilizer bomb plot in 2007, but cleared by police in any involvement in that plot. However, his links with the group does ask questions about whether he should have been permitted to travel to Syria by the British security services.
The radicalisation of the estimated 400 British Muslims that have gone to fight in Syria is a major worry for British intelligence services, as they are concerned they will become a direct threat to the UK.
In January, 16 people were arrested on suspicion of terror offences after travelling between Syria and the UK.