Up to 70 people have been killed in an attack on a house in Hama, according to Syrian activists.
They said several houses in the Masha at-Tayyar district in southern Hama were destroyed by a big explosion.
State media said 16 people died in the blast in a house used as a bomb factory by "armed terrorist groups".
Meanwhile, a video has emerged which purportedly shows a man being buried alive by security forces, allegedly for sending material to TV stations .
The unnamed man, who is said to be a media activist, is seen pleading for his life as earth is shovelled over his head. He then goes silent.
The security forces are heard cursing him for receiving money for sending material to Arabic satellite TV stations.
The video was leaked by sympathisers.