Hamas security forces and members of the Doghmush clan traded rifle and grenade fire west of Gaza City on Tuesday. Hamas said in a cryptic statement that its forces came under fire while on a mission in the area. The Doghmushes said the fighting began after Hamas came to arrest a clansman and confiscate his car. Ahab Ghussen, a spokesman for the Hamas-run Interior Ministry in Gaza, told The Associated Press that seucrity forces had surrounded a house in which several clansmen had holed up. "We will not return to the era of chaos," he said.