Hours after Palestinian factions announced their acceptance of an Egyptian-brokered cease-fire proposal on Wednesday, the Israel Air Force bombed a rocket-manufacturing plant in the Gaza Strip. Gazans said one person was killed and three were wounded in the strike on a metal workshop in the southern town of Rafah. One Palestinian witness said three helicopters hovered over the town and were fired at by Palestinians on the ground before the air strike took place. Also on Wednesday, the IDF imposed a full closure on the West Bank that will last through Holocaust Remembrance Day and end late Thursday evening. The IDF said it would allow Palestinians to enter Israel but only on a humanitarian basis and with approval from the civil administration. The Israel Police will raise its already heightened level of alert to "Special Level 3," and all leave will be canceled, for next week's Memorial and Independence Days. The alert level has been high since mid-April, and the police expects to continue what it calls "massive preparations" through mid-May, when US President George W. Bush will visit Jerusalem. "Our ultimate aim is to allow the public to celebrate and enjoy itself while providing a maximum sense of security, through a widespread deployment of officers and volunteers," the police said this week. Police will continue to be on the lookout for Palestinians who have illegally entered the country. Those who employ, transport or provide housing for them will also be targeted, and fixed and mobile roadblocks will be set up at the entrances to cities. Close to 20 Kassam rockets pounded the western Negev on Wednesday, with one scored a direct hit on the yard of a home south of Ashkelon, causing light damage and sending a woman into shock. She was taken to Barzilai Hospital. Earlier, a rocket struck near a school in Sderot, the second such incident in two days. On Monday, a Kassam slammed into a schoolyard in the city. No one was wounded in either attack.