International human rights watchdog Amnesty International warned Wednesday that the use of cluster bombs will lead to the indiscriminate killing of civilians, the day after the bombs were suspected of killing 33 civilians in central Iraq,

On Tuesday at least 33 civilians including many children were reportedly killed and around 300 injured in US attacks on the town of al-Hilla.

"Amnesty International is particularly disturbed by reports that cluster bombs were used in the attacks and may have been responsible for some of the civilian deaths," the organisation said.

"The use of cluster bombs in an attack on a civilian area of al-Hilla constitutes an indiscriminate attack and a grave violation of international humanitarian law," it said.

"If the US is serious about protecting civilians, it must publicly commit to a moratorium on the use of cluster weapons. Using cluster munitions will lead to indiscriminate killing and injuring of civilians," the organisation added.

On Tuesday, an AFP correspondent at Hilla south of Baghdad saw what seemed to be the parts of cluster bombs peppered over a large area. Hospital officials and witnesses said 48 civilians had died in US-British bombardment of the area since late Monday.

There was no independent confirmation of the death toll.

New York-based Human Rights Watch, in a report days ahead of the start of the current conflict, said cluster munitions dropped in the 1991 Gulf War were to blame for the deaths or injuries of more than 4,000 civilians after the fighting ended.