An attack in eastern Syria has killed at least 10 oil field workers, state news agency SANA has reported, a day after Syrian Kurdish-led forces announced an offensive against ISIL (ISIS).

“Two others have been wounded in a terrorist attack that targeted three buses transporting workers from al-Taim oil field in Deir Az Zor” province, the report said on Friday.

SANA did not provide any information on the nature of the attack or who may be behind it, but a British-based war monitor, in reference to ISIL,

accused “cells of the Islamic State group” of carrying out the assault near the oil field. The SANA news agency said that the attack targeted buses transporting workers in Deir Az Zor.

“The attack began with explosive devices that went off as the buses drove by, and then the group’s militants shot at them,” director of the Syrian Observatory for Human Rights, told AFP.

On Thursday, the Kurdish-led Syrian Democratic Forces (SDF) said they had begun an offensive against ISIL fighters

The operation is being carried out alongside the US-backed coalition, although there was no immediate confirmation from the international force that they were taking part.