IDF troops on Saturday attacked a group of Hamas terrorists firing mortar shells in the northern Gaza Strip, wounding two gunmen, Israeli and Palestinian officials said. Palestinian medics reported that one of the terrorists is in a critical condition. Witnesses said the clash occurred near the Nahal Oz fuel depot on the border between Israel and Gaza. The depot, which pumps fuel into Gaza, is a frequent target of Palestinian terrorists. Hamas said its gunmen were firing machine guns at the troops when they were struck. But local residents said the terrorists were firing mortar shells. The residents spoke on condition of anonymity, fearing retribution from Hamas. The army also said it had responded to mortar fire. Palestinian medical officials reported two wounded gunmen, including one in critical condition. Army Radio reported that IDF troops arrested two terror suspects during the Gaza operation. Earlier Saturday, at least eight projectiles, including both Kassam rockets and mortar shells, were fired at various areas in the western Negev from the Gaza Strip. No casualties or damage were reported in the attacks.