Shortly after Prime Minister Binyamin Netanyahu warned that every rocket attack from the Gaza Strip would be met by an Israeli response, Palestinian gunmen launched yet another mortar shell into Israeli territory - the fourth attack in the past twenty-four hours. Nobody was wounded and no damage was reported by the latest round, which landed nearby a group of IDF engineers working on the perimeter fence on the border of central Gaza. Earlier in the day, during an inauguration ceremony of a school in Kibbutz Shomriya, where a group of Gush Katif evacuees now lives, Netanyahu said, "We are not prepared to take more rockets, and we will respond like we did last night." The prime minister added that he hoped to complete the resettlement of disengagement evacuees into permanent homes in less than a year. His remarks came hours after IAF warplanes bombed a smuggling tunnel under the border of the Gaza Strip and Egypt. The IDF said that it launched the airstrike in response to a Kassam rocket which hit an open field near the Sdot Negev region on Sunday. No casualties were reported in the airstrike. Also on Sunday, two mortar shells struck near the Erez Crossing, just yards away from ambulances that were transferring a Palestinian heart patient to Israel for treatment. The ambulances were parked back-to-back inside the crossing as the mortars landed. Sick Palestinians cross almost daily into Israel for treatment in Israeli and overseas hospitals. Neither the Kassam rocket or the mortar shells caused casualties or damage. Herb Keinon contributed to this report.