An opposition leader, rights activist and longtime dissident in Syria's rebel-held city of Raqa has been abducted, a watchdog said Monday.
"The Syrian Observatory for Human Rights has learnt of the abduction by an armed group of lawyer, human rights activist and head of Raqa city's [opposition] local council Abdallah al-Khalil," the Britain-based group said.
"The Observatory condemns in the strongest terms the abduction of opposition lawyer Abdallah al-Khalil, and demands his immediate release," it said.
Khalil was abducted as he left the local council's headquarters in Raqa Sunday morning, added the watchdog, which relies on a broad network of activists, doctors and lawyers for its reports.
Syrian regime troops have not been inside the city since March this year, when Raqa became the first and only provincial capital to fall to rebel hands since the uprising against President Bashar al-Assad broke out more than two years ago.
The local council led by Khalil have worked with rebel groups and campaigned for the return of civilian life, despite frequent aerial attacks by the air force.
Khalil has been abducted before, telling Human Rights Watch researchers last month that he was held by security forces less than two months into the anti-Assad uprising.
He was transferred to 17 different security branches while in detention, HRW said.
Rights groups say tens of thousands of people are missing or in detention in Syria.