Ukrainian soldiers exchanged fired with insurgents who attacked a checkpoint in central Iraq, but no injuries or damage resulted, the Polish military said Thursday. Ten mortar rounds exploded close to the checkpoint north of Suwariyah late Wednesday, Polish Lt. Col. Artur Domanski said by phone from Iraq. The Ukrainians returned fire, forcing the attackers to withdraw, Domanski added. Poland commands about 6,000 troops in central Iraq from 15 countries, including about 1,650 Ukrainians.