Syria former prison guard: 'I showed them no mercy'

Ex-official gives rare first-hand account of Assad regime brutality

Dozens of former officials have spoken to the BBC about their role in the Assad regime's brutality, including a man who said he tortured detainees and then defected in 2012. The rare first-hand testimony forms part of a BBC investigation into Syria's notorious prisons under its former President Bashar al-Assad, who was overthrown last December. A UN report earlier this year said detentions and torture under the former regime constitute crimes against humanity.

Syrian human rights groups estimate that around 100,000 people disappeared under Assad's 24-year rule. The BBC has agreed to conceal the identities of the former regime officials it spoke to, to protect the value of their testimonies.