Tripoli, Libya (CNN) -- Forces loyal to Libyan leader Moammar Gadhafi have fired cluster munitions into residential areas in the besieged western city of Misrata, Human Rights Watch said Friday.
The organization said in a statement that it had seen three cluster munitions explode over the el-Shawahda neighborhood of Misrata on Thursday night. Researchers inspected debris from a cluster submunition and interviewed witnesses to two other apparent cluster-munition strikes, the statement said.
HRW inspected the submunition, which it said had been discovered by a New York Times reporter, and determined that it was a Spanish-produced MAT-120 120mm mortar projectile, which opens in the air and releases 21 submunitions across a wide area.
The submunitions explode on contact, disintegrating into molten metal that can strike people and penetrate armored vehicles, it said.
"It's appalling that Libya is using this weapon, especially in a residential area," said Steve Goose, arms division director at Human Rights Watch. "They pose a huge risk to civilians, both during attacks because of their indiscriminate nature and afterward because of the still-dangerous unexploded duds scattered about."
Most nations have banned their use through the Convention on Cluster Munitions, which became international law in August.
"Libya needs to halt the use of these weapons immediately, and take all steps to ensure that civilians are protected from the deadly remnants they have left behind," Goose said.