Syrian government troops and rebels have clashed around a prison in the flashpoint northern city of Aleppo.

According to BBC News, reports suggest the rebel fighters may have tried to blow up the walls of the prison, which holds some 4,000 inmates.

Activists said government forces had counter-attacked using tank shells and air raids.

Meanwhile, the rebel Free Syrian Army (FSA) vowed to punish criminals after a video appeared apparently showing a rebel biting a dead soldier's organs.

In Aleppo, rebels appear to have detonated car bombs outside the walls of the prison on Wednesday, May 15 morning, according to the Syrian Observatory for Human Rights (SOHR), a UK-based activist group.

Government sources claimed to have fought back, injuring and killing opposition fighters. Clashes were still continuing early on Wednesday afternoon.