At least 35 Palestinians and six Israelis have been killed in the deadliest spiral of violence since the conflict in the Middle East began more than 17 months ago.

The Israeli military has launched massive invasions into Palestinian-ruled areas in the West Bank and Gaza Strip as the violence in the region reaches unprecedented levels.

In a fierce land, sea and air offensive, Israeli forces pounded Palestinian targets following the killing of at least five Israeli teenagers by a Palestinian gunman who infiltrated a Jewish settlement in Gaza.

The students were killed by a Palestinian from the Islamic militant group Hamas.

Shortly afterward, Israeli combat helicopters and tanks opened fire on a village in southern Gaza killing at least 17 Palestinians, including a general, Ahmad Mefraj, in the security services.

Israeli warships blasted a police post in northern Gaza killing five Palestinians.

In the West Bank, Israeli soldiers raided Tulkarem, killing a least six Palestinians. One Israeli soldier was killed in Tulkarem.

Israeli forces swept into the biblical town of Bethlehem and surrounding areas, killing at least six people.

A Palestinian carrying explosives was shot and killed by Israeli border police in East Jerusalem's Beit Hanina neighborhood.

Police say the Palestinian was on his way to carry out a suicide attack in a nearby Jewish neighborhood built on disputed land.

Palestinian leader Yasser Arafat called for immediate U.S. intervention to stop what he called "the massacres" taking place in the Palestinian territories.

Palestinian negotiator Saeb Erekat said Israeli Prime Minister Ariel Sharon is determined to crush the current uprising without regard to how many people are killed.

"What we are witnessing out there are killing fields. It is a total escalation and is a war without any limitations as far as Sharon is concerned. He said that publicly. He said he will inflict the highest number of deaths on the Palestinians. This is his policy," Mr. Erekat said.

U.S. Middle East envoy and retired Marine Corps General Anthony Zinni is due in the region next week for another attempt to broker a cease-fire.

Israeli foreign ministry spokesman Ayre Mekel said he hopes Mr. Zinni's efforts are successful. "We welcome the visit of General Zinni. General Zinni is a friend and we are very hopeful that he can finally persuade the Palestinians to put an end to this wave of terror that they have initiated 18 months ago with the leadership of Chairman Arafat. We hope that Mr. Zinni will be able to put an end to it," Mr. Mekel said.

This past week has been the bloodiest since the Palestinian uprising against Israeli occupation erupted in September 2000.

More than 100 Palestinians and at least 35 Israelis have been killed so far.