Syrian activists say an explosion killed at least 11 people on a minibus carrying prisoners in Syria's northwestern province of Idlib on January 21.
The London-based Syrian Observatory for Human Rights gave no further immediate details and no independent confirmation was available.
In other violence, heavy fighting broke out between the Syrian army and soldiers who have defected to join anti-government insurgents in an area near the border with Turkey.
Al-Jazeera television said the clashes were in the city of Jisr al-Shughour.
compiled from agency reports