Heavy fighting in southern Lebanon stopped abruptly on Monday (August 14) after a U.N.-brokered truce came into effect, but the shooting of two Hizbollah guerrillas by Israeli soldiers underlined the fragility of the calm. Security sources in south Lebanon said Israeli air strikes and artillery fire continued until just a few minutes before the truce took effect at 0500 GMT. Then there was silence. The Israeli army said soldiers shot dead a Hizbollah fighter in southern Lebanon after he opened fire on them, the first casualty since the truce started. It said soldiers elsewhere shot another Hizbollah guerrilla who had approached them and aimed a gun at them. It was not known if he was killed. Israeli Defence Minister Amir Peretz said he would name a team to conduct a "wide and thorough" investigation of the Lebanon war. "As defence minister I plan to fulfil my part and to of course create a team that will conduct a wide and thorough investigation on all the incidents that erupted before the war and during (it)", Peretz said. Israel will keep pursuing Hizbollah leaders "everywhere and anytime" and will reserve the right to respond to any truce violations, Prime Minister Ehud Olmert said. "The leaders of this terrorist organisation have gone underground," Olmert told the Israeli parliament. "They will not get off free", he added. Around 1,100 people in Lebanon and 156 Israelis have been killed in the war that began after Hizbollah captured two Israeli soldiers in a cross-border raid on July 12. Israel says around 530 Hizbollah guerrillas were killed in the war. Hizbollah has acknowledged only about 80 dead.