IRAQI TROOPS REPORTED PUSHING BACK IRANIANS Iraq said today its troops were pushing Iranian forces out of positions they had initially occupied when they launched a new offensive near the southern port of Basra early yesterday. A High Command communique said Iraqi troops had won a significant victory and were continuing to advance. Iraq said it had foiled a three-pronged thrust some 10 km (six miles) from Basra, but admitted the Iranians had occupied ground held by the Mohammed al-Qassem unit, one of three divisions attacked. The communique said Iranian Revolutionary Guards were under assault from warplanes, helicopter gunships, heavy artillery and tanks. "Our forces are continuing their advance until they purge the last foothold" occupied by the Iranians, it said. (Iran said its troops had killed or wounded more than 4,000 Iraqis and were stabilising their new positions.) The Baghdad communique said Iraqi planes also destroyed oil installations at Iran's southwestern Ahvaz field during a raid today. It denied an Iranian report that an Iraqi jet was shot down. Iraq also reported a naval battle at the northern tip of the Gulf. Iraqi naval units and forces defending an offshore terminal sank six Iranian out of 28 Iranian boats attempting to attack an offshore terminal, the communique said.