Israeli troops operating against rocket squads in Gaza on Thursday killed a teenager who health officials and witnesses said was hit by shrapnel from a tank shell, then run over by an army bulldozer. Dr. Moaiya Hassanain of the Health Ministry in Gaza identified the youth as 17-year-old Mahmoud Kassassi. It was not immediately clear if he was armed. The Israeli army had no immediate comment on the incident, which took place during an Israeli incursion into central Gaza. Hamas security forces said dozens of jeeps, tanks and bulldozers moved about 1.5 kilometers (1 mile) into the strip. Earlier Thursday, two Hamas fighters were seriously injured in clashes with Israeli troops in the same area, Hamas said. The army said troops had been exchanging fire with militants, hitting one. The Associated Press quoted the army as saying that it faced an anti-tank missile with no injuries. On Wednesday, the Israeli government designated Gaza a «hostile territory,» threatening to cut back vital supplies of fuel and electricity if the rocket attacks continue. The decision drew condemnation from Palestinians who said it would deepen the hardship of Gaza's already impoverished residents.