JERUSALEM, June 13 (JTA) — The fragile peace efforts launched last week at the Middle East summit in Aqaba, Jordan, appeared to be unraveling at a dizzying pace as Israel and the Palestinians were drawn back into a familiar and bloody pattern of violence and retaliation. Israeli officials said Friday they would step up military actions against Hamas, announcing that all of its leaders would be considered potential targets. An Israeli security source said the Defense Ministry had ordered the army “to use everything they have” against the terror group. Even as they went into hiding, Hamas leaders vowed that the organization would intensify its terrorist campaign against Israel. On Friday, Palestinians fired a rocket at the Negev town of Sderot, which sent seven Israelis into shock when it crashed through the roof of a house and into a family’s living room. Late Friday, Israeli helicopters fired rockets at a car in the Gaza Strip, killing Hamas member Fuad Ledawi and wounding at least 20 Palestinians. Israel said the car’s occupants had fired rockets into Israel. Israeli television reported that an Israeli was killed Friday evening in a shooting in the West Bank city of Jenin, but gave no details. Israel and the Palestinian Authority agreed late Friday to renew security contacts, beginning with a meeting Saturday evening. The decision was made following pressure from the United States and Egypt, the Israeli daily Ha’aretz reported. Israel on Thursday began burying victims of Wednesday’s bus bombing in downtown Jerusalem, which killed 17 people and wounded more than 100. Among the wounded was Sarri Singer, daughter of New Jersey State Sen. Robert Singer. She had stayed in Israel after participating in the birthright israel program. After the bombing, Israel carried out raids from helicopter gunships against wanted Hamas members. Among those killed were Massoud Titi, a senior leader of Hamas’ military wing and the person Israel believes was behind the group’s Kassam rocket firing; Suhil Abu Nahel, an aide to Hamas spiritual leader Sheik Ahmed Yassin; and Yasser Taha, a senior Hamas member. A number of Palestinian civilians were killed and injured in the strikes. Israel insisted that the airstrikes were planned before Wednesday’s bus bombing — when a terrorist dressed as a fervently Orthodox Jew blew himself up on a bus in downtown Jerusalem — and were not a direct response to the attack. Killed in Wednesday’s bombing were Miriam Levy, 74, of Jerusalem; Yaniv Obayed, 22, of Herzliya; Sgt. Tamar Ben-Eliahu, 20, of Moshav Paran; Eugenia Berman, 50, of Jerusalem; Elsa Cohen, 70, of Jerusalem; Zvi Cohen, 39, of Jerusalem; Roi Eliraz, 22, of Mevasseret Zion; Anna Orgal, 55, of Jerusalem; Alexander Kazaris, 77, of Jerusalem; Tita Martine, 75, of Jerusalem; Yaffa Mualem, 65, of Jerusalem; Bet-El Ohana, 21, of Kiryat Ata; Zippora Pesahovitch, 54, of Tsur Hadassah; Bianca Shahrur, 62, of Jerusalem;Malka Renee Sultan, 67, of Jerusalem; and Alan Beer of Jerusalem, 47, who immigrated from Cleveland in 1998. The last victim, a man, had not been identified as of Friday. U.S. Secretary of State Colin Powell on Friday urged Israel to exercise restraint in responding to Palestinian terrorism. “We all are anxious to see restraint and we understand that it’s important to get the terror down,” Powell told reporters. “If the terror goes down, then the response to terror will no longer be required, so we have to get moving and bring the terror down.” Also on Friday, the Palestinian Authority prime minister, Mahmoud Abbas, told President Bush that he would resume efforts to persuade terrorist organizations to declare a cease-fire so the “road map” peace plan could be implemented. Hamas, however, warned all foreigners to leave Israel for their own safety, and threatened to assassinate Israeli Prime Minister Ariel Sharon. “The Jerusalem attack is the beginning of a new series of revenge attacks” in which Hamas “will target every Zionist occupying our land,” the group said in a statement faxed to Reuters. “We call on international citizens to leave the Zionist entity immediately to preserve their lives.” Powell is preparing to meet in Jordan on June 22 with leaders of the United Nations, Russia and the European Union — the bodies that helped the United States draft the “road map” — in an effort to repair the tattered peace plan, U.S. and diplomatic sources said Thursday. The meeting will be held in Aqaba, where Bush met last week with Sharon and Abbas to kick off implementation of the plan. Powell on Thursday told reporters that “it is incumbent on every nation around the world to speak out and put the hammer down on Hamas, the PIJ” – Palestinian Islamic Jihad – “and stop funding them, stop allowing any resources to go to them.” Condemning the bombing on Wednesday, Bush urged the parties to work to end the bloodshed. He also called on countries that want peace in the Middle East to fight terrorism and stop the flow of funds to groups like Hamas. The suicide bombing and Israel’s airstrikes capped a bloody week. At least five Israelis were killed and five wounded in separate incidents in the Gaza Strip and West Bank on Sunday. Israel responded to those attacks on Tuesday, when it launched a helicopter strike in Gaza City that wounded its intended target, senior Hamas official Abdel Aziz Rantissi, and killed two bystanders. The strike on Rantissi, which prompted Bush to issue Israel a stiff rebuke, came a day after Sharon began fulfilling Israel’s obligations under the road map, removing some 10 illegal outposts in the West Bank, most of them unpopulated. Though the United States defines Hamas as a terrorist group, Bush criticized Israel’s strike against Rantissi, saying it “does not contribute to the security of Israel.” Israelis had been bracing for possible terrorist retaliation since the failed assassination attempt. Israel says Rantissi serves as the head of Hamas’ military wing and believes he played a vital role in organizing Sunday’s attack in the Gaza Strip that killed four Israeli soldiers. Wednesday’s bombing occurred during rush hour, at around 5:30 p.m., as Egged bus number 14A was making its way up Jerusalem’s Jaffa Road toward King George Street. The bomber blew himself up as the bus was near a stop in front of a large office building not far from the Mahane Yehuda outdoor market. Reports said the bomber wore a kipah and ritual fringes to pass as a fervently Orthodox Jew. Ibrahim Atrash, the Israeli Arab driver of the bus, was lightly wounded in the attack. He said he had noticed nothing unusual about any of the passengers. “Today I didn’t see anyone suspicious. If I did, I would have questioned them before letting them board,” the Israeli daily Yediot Achronot quoted him as saying. Police said the bomb used in the attack was large and packed with nails and metal pieces to maximize casualties. Unfazed by international criticism of the assassination attempt, Sharon said Israel would not compromise its fight against terrorism. “Israel will pursue to the end Palestinian terrorist organizations and their leaders,” including “those who initiate, finance and dispatch terrorists,” Sharon said Wednesday evening. “We have a deep commitment to make every effort to advance a political process that will bring – we hope – peace and quiet. We will take every step to protect the security of Israeli citizens.” Several P.A. officials voiced responses to the attack. Abbas urged Israel and the Palestinians to work toward implementing the road map. In unusually explicit language, P.A. President Yasser Arafat condemned the “terrorist attack in Jerusalem,” while also denouncing as terrorism Israel’s attack on Rantissi. Other P.A. officials blamed Israel for the recent escalation, accusing the Sharon government of deliberately sabotaging peace efforts.