CONAKRY, Sept 30 (Reuters) - Guinea's military ruler Captain Moussa Dadis Camara has promised an inquiry into a crackdown by security forces on opposition protesters which local rights groups said claimed at least 157 lives. But Camara, speaking on state television last night, said opposition troublemakers would be punished and accused crowds at Monday's rally in the capital Conakry of looting weapons from a police station. "(Authorities) will do all necessary to shed light on these tragic events which threaten social peace," he said. In a warning to opposition leaders, he added that any further "subversive" meetings were banned. Camara seized power in December 2008 after the death of President Lasana Conte. He promised to ensure transition to civilian rule but has recently angered critics by not ruling out standing in a January election. Monday's violence, the worst since the December coup, drew broad international condemnation. Former colonial power France said it had cut military cooperation with Guinea and would discuss further measures with European partners on Wednesday. A senior official at one of Conakry's hospitals went on state television to announce an official death toll of 52 -- a third of the figure estimated by a local rights group quoting hospital sources. (Reporting by Saliou Samb; Writing by Mark John; Editing by Louise Ireland)