The employees and contractors work for a cement company
Islamic State militants have kidnapped 300 workers near the Syrian capital Damascus, according to state TV.
The cement company employees and contractors were taken from an area where militants launched a surprise attack against government forces earlier this week.
Workers were reportedly taken from a dormitory where they were staying on the outskirts of the town of Dumeir.
A factory administrator said no-one had been able to contact the workers since the assault on Monday.
Meanwhile, there are separate reports Syrian rebels have managed to seize control of Islamic State's main supply route to Turkey.
Humanitarian organisation Médecins Sans Frontières (MSF) says the situation remains critical in many besieged areas, despite a cease-fire and humanitarian convoys gaining access.
Last week, two MSF-supported field hospitals, a nearby school and inhabited buildings in besieged East Ghouta suburbs were bombed.
At least 38 people were killed and 87 wounded, of whom five wounded were medical staff.
Dr Bart Janssens is the MSF director of operations.
He says some areas are still seeing "catastrophic" consequences.