Israeli troops rolled into northern Gaza Tuesday, sparking the deadliest fighting with local militants in more than a year and killing at least 19 Palestinians, including two killed in the evening in an airstrike in the northern Gaza Strip, DPA reported. Another 45 people were injured, 12 of them seriously, hospital officials said. In the latest strike, a group of militants belonging to the Mujahidin Brigades of the Fatah movement were launching homemade rockets from northern Beit Hanoun at the Israeli town of Sderot, when they were struck by a missile fired from an Israeli aircraft.