The IDF is checking to see whether the terrorist killed in Gaza in an Israeli air strike on Sunday night belonged to Hamas, a senior security source said Monday morning. Hamas has announced that the casualty was a member of its military wing."We know unequivocally that the terrorist killed in the strike was preparing to fire rockets," the source added.The security source noted that a Givati infantry unit operating along the Gaza border came under fire on Sunday as well.Hamas has not been behind recent rocket attacks on southern Israel, but rather, smaller terrorist groups in the Strip, according to military assessments. "[But] we are more interested in who is responsible [for Gaza]," he added."We are weighing our steps and managing a responsible policy on all aspects linked to Gaza," the source said. "We understand that this rocket fire is becoming daily. Our responses are in accordance to that. The policy of the Southern Command is a policy of escalating responses, both in scope and the quality of targets," he added.The IDF is aware of the fact that Hamas has a problem in restraining smaller Gazan terror groups from firing rockets, the source stated, "but we also understand that the motives are less interesting, and the results are what count," he added. "Our desire is to stop this rocket fire."