A shocking video of a suicide attack against a Syrian prison, which UK officials believe was carried out by a British jihadist, has emerged.
The 4-minute video shows Islamist fighters with the al-Qaida-linked Jabhat al-Nusra rebel group, as they lay siege to a government jail in Aleppo last week.
An explosive-laden truck fitted with home-made armour plates is seen driving at high speed into the prison's walls, before detonating.
In the second part of the footage rebel fighters fire heavy weapons and small arms at the prison.
Jabhat al-Nusra said the suicide driver was called Abu Suleiman al-Britani, a pseudonym indicating the jihadist's British origins.
British police and the MI5 have opened an investigation to ascertain the man's identity.
Detectives reportedly believe al-Britani was a British national from the Crawley area, Sussex.
If confirmed, the suicide attack would be the first carried out by a Briton in Syria.
The attack was part of a rebel operation to take over the prison in the northwestern Syrian city, believed to be holding several thousands of rebel prisoners.
Rebels said the attack was unsuccessful as the explosion apparently failed to blow up the prison's walls.
The detention complex has been the site of heavy fighting between forces loyal to Syrian president Bashar al-Assad and rebel groups in recent months.
The British-based Syrian Observatory for Human Rights said that regime forces regained control of most of the prison, while fighting was continuing on its outskirts.
Hundreds of Britons are believed to have travelled to Syria to take part in the civil war that has as killed more than 100,000 people since 2011.