Syrian government forces and allied armed groups recaptured a gas field from Islamic State fighters on Thursday, a monitoring group said.
The Sha'ar gas field in central Syria has changed hands four times since July, when Islamic State fighters first seized it and killed about 350 government troops, allied militiamen, guards and staff, according to the Britain-based Syrian Observatory for Human Rights.
Government forces retook the field, which lies to the east of the central city of Homs, later that month but lost it again to Islamic State last week in fighting that killed at least 30 pro-government fighters.
The Observatory did not give casualty figures or further details for Thursday's fighting when pro-government forces again retook the field.
Clashes between forces loyal to President Bashar al-Assad and Islamic State were relatively rare until the summer, when the jihadists began taking government bases including several in the northern province of Raqqa.
The two sides have continued fighting as U.S.-led forces began bombing Islamic State in Syria in September. The United States says it is not coordinating with Assad's forces.