Israeli troops traded heavy gunfire with Palestinians in a raid near this refugee camp Sunday, killing 15 Palestinians in the deadiest confrontation in Gaza (search) in 17 months.

The raid came a day after Palestinian militants staged an elaborate shooting and bombing assault on a Gaza checkpoint. The military said it was looking for weapons in the Bureij camp, but found none and made no arrests. The raid apparently was also meant to draw out the militants, a possible new tactic by the military ahead of a Gaza withdrawal.

"Terrorism is pouring out of this refugee camp, and we have to stop it," Israeli government spokesman Avi Pazner said. "We believe that by doing so we have prevented acts of terror in Israel and saved many human lives."

The dead included 10 gunmen, all but one from the militant group Hamas (search). Three boys were among the dead as well.

The fighting pitted hundreds of Palestinians armed with assault rifles, anti-tank missiles and grenade launchers against Israeli troops firing from helicopters, tanks and rooftop sniper positions. Palestinian children chased after Israeli tanks and jeeps, throwing stones.

The violence was part of a new wave of fighting in Gaza, with each side trying to make a proposed Israeli withdrawal from the strip look like a victory.

Prime Minister Ariel Sharon (search) has said he would evacuate most Gaza settlements if peace efforts do not bear fruit soon, but Israel has been expected to intensify military strikes beforehand to avoid giving the impression it is fleeing.

Militants, meanwhile, have said they were stepping up attacks to show they are forcing Israel out of Gaza.

Palestinian Cabinet minister Saeb Erekat called for a return to negotiations on the U.S.-backed "road map" peace plan. "At a time when they're speaking about withdrawing from Gaza, they're destroying Gaza," Erekat said.

On Sunday afternoon, tens of thousands joined the funeral procession for the dead. Hundreds of gunmen firing in the air led the crowd, to chants of "resistance and holy war until we uproot the last Zionist invaders from our sacred soil."

One Hamas gunman told mourners that the militants are sending a message to Israeli Prime Minister Ariel Sharon that "we are ready for confrontation."

Women on balconies threw candy into the crowd.

The raid began before dawn Sunday when Israeli forces, with at least two Apache helicopter gunships hovering overhead, moved slowly down alleys and side streets on the outskirts of the Bureij and Nusseirat refugee camps.

Israeli troops withdrew by midmorning, but the pullback was slowed by militants chasing them with rocket propelled grenades and mortars. An earthmover got stuck and was attacked by dozens of homemade missiles, the army said.

Palestinian sources said the Israeli raid cut telephone and electric lines to central Gaza and damaged a fuel storage depot.

Sunday's raid was the deadliest in Gaza since October 2002, when 19 Palestinians were killed in fighting in the Khan Younis refugee camp.

On Saturday, three Palestinian militant groups attacked the Erez Crossing between Gaza and Israel, sending a homicide bomber and militants with assault rifles in vehicles disguised as a taxi and two Israeli army jeeps to attack soldiers guarding the heavily fortified area. Four Palestinian assailants and two Palestinian policemen were killed in the attack. No Israelis were hurt.

Israel closed the crossing, used by 19,000 workers who cross in to Israel, in response to the attack.

Lt. Gen. Moshe Yaalon, the Israeli army chief, said a decision would be made soon about when to reopen Erez, the target of three deadly attacks since Jan. 24.

"If we see that the terror groups don't let up, we will have to reconsider," he said.

Hamas, Islamic Jihad and the Al Aqsa Martyrs' Brigade, a militant group linked to Yasser Arafat's Fatah faction — claimed joint responsibility for Saturday's attack.

Pazner denied a link between the stepped up Israeli raids and the planned withdrawal. "We are now fighting terrorism. This has nothing to do with any future plan about Gaza," he said.