A top Palestinian security leader who is a related to Yasser Arafat (search) escaped unharmed on Tuesday when a booby-trapped car exploded near his convoy in Gaza City.

The blast came as Israeli Prime Minister Ariel Sharon (search) tried to cobble together a governing team to carry out his plan to withdraw from Gaza (search) next year.

The bomb rocked Gaza City after nightfall, as Moussa Arafat's convoy was leaving his headquarters. Arafat, a cousin of the top Palestinian leader, was not hurt, security officials said. As the convoy sped off, Moussa Arafat's body guards fired submachine guns in the air.

Israel's military denied involvement. It appeared more likely that local opponents were responsible, though no one claimed the attack. Palestinian riots torpedoed Yasser Arafat's attempt to appoint his relative as head of Gaza security in July.

In a statement, Moussa Arafat called the bombing an assassination attempt, but he did not name suspects. Last year he escaped injury in an explosion in his office, when he said Palestinian enemies fired a rocket at the building.

Early Wednesday, Israeli troops operating in northern Gaza the last two weeks moved into a new area near the town of Beit Lahiya, residents and military sources said.

Witnesses said an Israeli drone aircraft fired a missile at a house, killing a Hamas militant and seriously wounding three gunmen. The military had no comment.

Israeli military sources said the air force spotted armed militants at the entrance to Beit Lahiya and hit them in an air strike.

The Tuesday bombing was more evidence of chaos inside Gaza as the planned Israeli withdrawal approaches. Armed groups are vying with each other, and the official security forces, weakened during four years of conflict with Israel, are unable to assert authority.

Moussa Arafat was one of the members of a senior Palestinian security delegation that met with Egyptian officials in Cairo for four days last month about Sharon's planned withdrawal of troops and settlers from the Gaza Strip.

Egypt pledged to train Palestinian police ahead of the Israeli withdrawal from Gaza. Palestinian Interior Minister Hakam Balawi said Egypt would train 45 Palestinian security officers for six to 10 weeks.

Sharon's political problems threatened to scuttle his Gaza pullout plan. With the first parliamentary vote on the withdrawal just weeks away, it appeared likely Sharon will have to rely on the moderate opposition Labor Party — an alliance that threatens to tear apart his own faction.

The fissures in Sharon's Likud Party were visible during the prime minister's policy speech to parliament Monday night, in which he defended his Gaza pullout plan. In a symbolic vote, roughly a quarter of the Likud's lawmakers rejected the plan.

Sharon plans to dismantle all 21 Jewish settlements in Gaza and four small enclaves in the West Bank next year. After four years of fighting with the Palestinians, Sharon says the plan will boost Israel's security and head off international efforts to force Israel to make deeper concessions.

Opponents, including critics within the Likud, accuse Sharon of caving in to Palestinian violence and fear his plan is just the beginning of a larger withdrawal from the West Bank.

Over the heckling of hard-line lawmakers, Sharon told the noisy parliament he would present the pullout plan for approval on Oct. 25.

While Sharon is expected to survive that vote, the long-term prospects for his coalition are dim. Sharon faces further parliamentary votes on the withdrawal as well as a contentious budget battle.

Opposition to the Gaza plan has already left Sharon with a minority coalition, meaning he will have to seek new partners or call early elections as he pushes forward with his agenda. The next elections are scheduled for late 2006.

Sharon said Tuesday he wants to avoid elections, which would likely delay his withdrawal plan for months.

"The current political situation can't continue, but I will do everything to prevent early elections," he was quoted as saying during a meeting with Justice Minister Joseph Lapid.

In an initial effort to expand the coalition, Sharon dispatched his defense minister, Shaul Mofaz, to meet with the spiritual leader of Shas, an Orthodox Jewish party that has so far withheld support for the Gaza plan. No agreements were reached, but officials said more meetings were likely.

It was the first of many feelers Sharon is expected to put out as he tries to shore up his government.

People close to Sharon said he would meet with other Orthodox Jewish parties and Labor, the main opposition party.

Vice Premier Ehud Olmert, who is close to Sharon, told Channel Two TV, "We can't have a situation where the prime minister has one policy and some of his ministers have another."

Dalia Itzik, a senior Labor lawmaker, said the party's 21 lawmakers will support Sharon when he brings the Gaza plan to a vote. She also said the party would be willing to join the government to prevent its collapse.

"If we see that he won't have a government without us, we'll help him," she told reporters.

Expanding the government — with either Labor or Shas — could spell trouble for Sharon.

The Likud has voted against adding Labor to the government. Bringing in Orthodox Jewish parties would alienate the secular Shinui, now Sharon's main coalition partner.

In violence Tuesday, a 10-year-old Palestinian girl was shot in the stomach and critically wounded by Israeli gunfire as she sat at her desk inside a United Nations school in a southern Gaza refugee camp, U.N. officials said.

The army said its troops opened fire in the area after a Palestinian mortar attack and was investigating the shooting.