Syrian activists say the Islamic State group has retaken a strategically important town in the central province of Homs from government forces.
The government had recaptured the town of Mahin and surrounding villages from the extremists two weeks ago as part of a general offensive to secure the highway connecting Damascus to the country's northwest.
The loss deals a setback to the Syrian army's strategy to fortify the corridor with support from Russian airpower.
The London-based Syrian Observatory for Human Rights says that fighting is underway on Thursday between IS militants and government forces with their allied militias outside of Mahin.
Islamic State media outlets reported earlier that the group's fighters had seized the hills overlooking the town on Wednesday night.