A powerful type of cluster munition rocket not previously seen in the Syrian conflict is possibly being used by regime forces, Human Rights Watch said in a statement on Wednesday.

Basing its statement on photos taken after a recent attack in the central city of Hama, HRW said the images suggested the government had deployed 300 mm 9M55K surface-to-surface rockets.

The weapon, which carries dozens of submunitions, is Russia, according to Agence France-Presse.

The rockets were identified as having been used on Feb. 12 and 13 in attacks that killed at least two civilians and wounded at least 10 others, AFP reported, citing the rights group.

"It is appalling that Syrian government forces are still using banned cluster munitions on their people," said Steve Goose, arms division director at Human Rights Watch.

"Cluster bombs are killing Syrian civilians now and threatening Syrians for generations to come."

Cluster bombs have been banned by 113 countries around the world.

They are particularly controversial because they are indiscriminate and the bomblets they carry are often widely dispersed and continue to maim and kill civilians long after the initial attack.

(Al Arabiya With AFP)