A bomb blast in north-western Syria killed an officer and three soldiers on Monday, activists said, reported dpa.
"Gunmen, suspected of being army defectors, blew up a bomb by remote control as an army vehicle passed by Ihsem town, in the countryside of the northwestern province of Idlib," Rami Abdel Rahman of the London-based Syrian Observatory for Human Rights told dpa.
The blast also left several others injured.