Jerusalem ? Israeli aircraft Wednesday fired two missiles at a car on a crowded urban road in the Gaza Strip, wounding a Hamas militant, killing two bystanders and bringing denunciations from Palestinian groups that reportedly are close to declaring a cease-fire.

The missile attack in Khan Yunis, which the Israeli army said was aimed at a car carrying Hamas militants and loaded with rockets or mortar shells, left 15 other people wounded, Palestinian officials said.

Hamas leaders and other Palestinians demanded that Prime Minister Ariel Sharon cease the Israeli policy of targeted assassinations.

“Every time we get close to a decision (on the cease-fire) there is the response of the killer Sharon,” fumed Ismail Haniyeh, a senior Hamas leader.

Palestinian officials mediating among the various extremist groups declared Wednesday that a deal had been reached that would impose a three-month moratorium on attacks on Israeli targets. But the emerging agreement was surrounded by questions, as no militant group appeared willing to be the first to embrace it.

Leaders of Hamas, which has carried out many of the deadliest attacks on Israeli civilians, strenuously denied that anything had been made final. Islamic Jihad, which is also responsible for terrorist acts within Israel, had all but announced a deal Tuesday before quickly back-pedaling.

Ending the violence is a prerequisite for the U.S.-led “road map” peace plan, which envisions an Israeli military withdrawal from many Palestinian areas and the establishment of a Palestinian state by 2005.

President Bush, siding with Israel, is pressing Palestinian Prime Minister Mahmoud Abbas to disarm Hamas and other groups. Abbas is instead negotiating, arguing that confronting the militants would lead to a Palestinian civil war.

“It’s one thing to make a verbal agreement,” Bush said in Washington after word of the apparent cease-fire became public. “But in order for there to be peace in the Middle East, we must see organizations such as Hamas dismantled.”

The fate of the cease-fire was thrown into further question by Wednesday’s violence, which started early.

While U.S. special envoy John Wolf discussed security arrangements at a morning meeting with Abbas in Gaza City, a few miles away, Israeli soldiers shot dead two Palestinians. The army said the dead were members of Hamas raiding party targeting an Israeli army outpost in Beit Hanoun on the Gaza-Israeli border.

The army said Hamas gunmen at Beit Hanoun had barricaded themselves inside a house and battled Israeli soldiers for hours. Hamas said the raid was to avenge Israel’s killing of regional Hamas commander Abdullah Kawasme last weekend in Hebron.

In Israel fear of Palestinian reprisals ran high Wednesday after Israeli police arrested two Palestinians carrying a bomb in an Arab-Israeli town. Police allege the two men were on their way to carry out a suicide mission in central Israel.

An Israeli army spokesman said the target of the missile strike at Khan Yunis was Mohammed Siam, 34, who had been on his way to fire Qassam rockets at Katif, a cluster of settlements near Khan Yunis.

Witnesses said Siam and three other men leapt from their car when the first missile missed. But the impact of a second missile tore off Siam’s leg and he remained in critical condition, hospital doctors at Khan Yunis said.

The witnesses said the second missile, fired either by an Apache helicopter or an F-16 fighter they heard swooping down on the town, hit a taxi driving behind Siam’s car. The impact killed the taxi driver, Akram Abu Faharan, 32, and his passenger, Niveen Aburujella, a 22-year-old female.

Israel has been under international pressure to abandon its assassination policy, which has led to many civilian deaths. But Sharon told his Cabinet this week he would not suspend what he calls “track-and-kill” missions against “ticking time bombs” Palestinians identified by Israeli security as likely to carry out terrorist acts.