New York-based Human Rights Watch reports evidence of a deadly additional threat to Syrian civilians from the use of cluster bombs by government forces in their battles against rebels.

Such weapons are banned by most countries because of the danger they pose to civilians.

A Human Rights Watch report says Syrian activists posted at least 18 videos showing remnants of the bombs in or near several towns. Many were on a north-south highway that has been the scene of fighting in recent days.

Cluster bombs scatter small bomblets over a wide area. Many bomblets do not immediately explode, posing a threat to civilians for long afterward.

Human Rights Watch said the munitions in the video were Soviet-made. Before its collapse, the Soviet Union was a major arms supplier to Syria.

It is nearly impossible to independently verify such reports in Syria.

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