Baghdad, May 17, SPA -- U.S. troops backed by attackhelicopters and militants clashed in this northern city onTuesday with heavy exchanges machine gun fire being heard,the U.S. military and an Associated Press reporter at thescene said. U.S. forces were seen advancing into the easternneighborhood of Dhubbat, a known insurgent stronghold inMosul, 360 kilometers (225 miles) northwest of Baghdad, theAP reporter said. "Forces were attacked and called in helicopters tosupport them in the battle with insurgents," said U.S.military spokesman Sgt. John H. Franzen. He did not havefurther details. Heavy machine gun exchanges were taking place in the areabetween militants and U.S. forces, said the AP reporter whowitnessed the clashes from the rooftop of a nearby home.American helicopters were also seen circling overhead.--SPA1514 Local Time 1214 GMT www.spa.gov.sa/263050