COLOMBO, Sri Lanka (AP) âÄî The Sri Lankan government says it will stop using heavy weapons and air strikes in the northern war zone to prevent further casualties among the civilians there. In a statement Monday, the government said it concluded that combat operations had reached their conclusion and its troops would no longer use heavy machine guns, air strikes or artillery in the battle against the Tamil Tiger rebels. The statement came amid heavy international pressure for a cease-fire to protect the tens of thousands of civilians trapped in the war zone. The government rejected a rebel truce appeal on Sunday as a desperate bid to stop the offensive.