At least three people were killed and 20 wounded in an explosion of unknown origin on Monday at the entrance to the town of Abu Kamal in the eastern Syrian of Deir ez-Zor governorate, Xinhua news agency reported, citing state media.

Authorities have not yet determined the cause of the blast, and no group has claimed responsibility.

The strategically important border town of Al Bu Kamal, located near the border between Syria and Iraq, has been the target of previous attacks which were often attributed to remnants of the Islamic State operating in the region.