Activists: Wave of tit-for-tat kidnappings between rebel groups in Syria's Aleppo

This citizen journalism image provided by Edlib News Network, ENN, which has been authenticated based on its contents and other AP reporting, shows black smoke rising from what rebels say is a helicopter that was shot down at Abu Dhour military airbase which is besieged by the rebels, in the northern province city of Idlib, Syria, Friday May 17, 2013. Rights activists have found torture devices and other evidence of abuse in government prisons in the first Syrian city to fall to the rebels, Human Rights Watch said in a report Friday. (AP Photo/Edlib News Network ENN) (The Associated Press)

BEIRUT – Syrian activists say that a wave of tit-for-tat kidnappings between rival Islamic militant groups in the northern city of Aleppo risks sparking large-scale internal fighting between rebels.

Rami Abdul-Rahman, who heads the Britain-based Syrian Observatory for Human Rights, said Saturday that a coalition known as the Judicial Council had accused another rebel force, the Ghurabaa al-Sham, of robbing factories in Aleppo's industrial neighborhood.

He said the two groups clashed on Tuesday and the Judicial Council is now holding Ghurabaa al-Sham members captive. The Ghurabaa al-Sham is also holding Judicial Council members.

Aleppo-based activist Mohammed Saeed said Ghurabaa al-Sham withdrew its fighters from several neighborhoods, including the industrial area.

Aleppo is Syria's largest city and is split between rebel and government control.