Updated

Activists say Syrian government forces have launched a counter-attack to recapture a gas field seized by Islamic extremists, as the death toll from three days of fighting rises to more than 200.

The Britain-based Syrian Observatory for Human Rights says special forces launched an attack late Friday on the Shaer field in the central province of Homs and regained parts of it.

A Homs-based activist who goes by the name of Beibares Tellawi confirmed Saturday that troops were attacking fighters from the Islamic State group.

The Observatory said that the number of troops, guards and workers killed in the gas field since it was captured Thursday has risen to 270. Tellawi said the death toll was at least 200.

The fate of 90 others is still unknown, the Observatory said.