At least 30 Syrian soldiers were killed by the explosion of a powerful bomb in a long tunnel that scores of rebels spent weeks digging under a checkpoint, a monitor said Tuesday.
"Around 30 regime forces were killed... in a blast (Monday) in which several tons of explosives were planted in a tunnel beneath a checkpoint on the northeastern outskirts of the town of Maaret al-Numan,"the Syrian Observatory for Human Rights said.
A video posted online by Syria's biggest rebel alliance, the Islamic Front, showed an enormous explosion ripping open the ground and throwing huge quanties of earth and debris dozens of metres (yards) into the air.
A rebel in Idlib province told AFP via the Internet that 60 rebels had spent 50 days digging the tunnel.
Signup to our newsletter and follow us on Facebook and Twitter!
"After the explosion, the fighters raided the checkpoint, which was composed of three buildings," said the rebel, who identified himself as Abu Leila.
Opposition fighters have regularly made use of tunnels to facilitate their movement and to attack government facilities, setting off explosive charges under checkpoints and headquarters.
Rami Abdel Rahman, director of the Britain-based Observatory, said the checkpoint was one of the lines of defence for the Wadi Deif military base, one of the last regime strongholds in Idlib.
Rebels have been trying for more than a year to capture Wadi Deif and the nearby Hamadiyeh military base, but the regime has thus far repulsed their attacks.