The international Red Cross, guardian of the Geneva Conventions on the laws of warfare, called Monday for an immediate end to the type of cluster bombs that have had what it called "horrific" consequences in such places as southern Lebanon. Philip Spoerri, director of international law for the International Committee of the Red Cross, said countries needed urgently to address the bombs, which are still killing or injuring Lebanese civilians every week. "It is simply unacceptable that (civilians) should return to homes and fields littered with explosive debris," Spoerri said. "Cluster munitions are often the worst offenders given the massive numbers in which they are used, their area-wide effects and their well-known problems of accuracy and reliability." The clusters contain tiny bombs - or submunitions - which are packed into artillery shells or bombs dropped from aircraft. A single cluster-bomb canister fired to destroy airfields or tanks and soldiers typically scatters some 200 to 600 of the tiny bombs over an area the size of a football field.