KHAN YUNIS, Gaza Strip — Palestinian militants killed three Israeli soldiers Saturday in a daring raid on an army outpost in the southern Gaza Strip, and three Israeli civilians were shot dead when their car was ambushed near Jerusalem.

The deaths prompted Israel to send tanks, armored personnel carriers and bulldozers into Palestinian areas in the Gaza Strip. The Israelis destroyed a security building and several security checkpoints before withdrawing early Sunday.

Three Palestinians were also killed — the two militants who carried out the raid on the Israeli military outpost, and a police sergeant hit by Israeli tank fire during the subsequent incursion into Palestinian areas in Gaza, Palestinians said.

"Whether attacking Israeli soldiers in Gaza or attacking Israeli civilians on roads near Jerusalem, Yasser Arafat is escalating his war of terrorism against the state of Israel," said Israeli government spokesman Dore Gold.

Israeli Prime Minister Ariel Sharon had said Israeli forces would respond swiftly to Palestinian attacks, and the army focused its attention on Rafah, a town in southern Gaza near the border with Egypt. The town is only a few miles from the Israeli military outpost in Marganit that came under assault Saturday.

The Israelis briefly took over several small Palestinian security outposts, and bulldozers tore down the headquarters of Palestinian Public Security, according to residents and Rafah's Governor Majid al-Ajha.

The Israeli tanks and armored vehicles came under heavy Palestinian gunfire, and shot back with shells and machine guns, they added. The police sergeant, Alla Abu Bakra, was killed by shrapnel, and at least two more Palestinians were wounded, doctors said.

At mosques in Rafah, calls went out over the loudspeakers urging residents to join a "holy war" against the Israeli forces.

"The people of Rafah are defending the city in order to teach the Israelis a lesson," said al-Ajha.

At around 3 a.m. Sunday, the Israeli forces began withdrawing from Rafah, residents and officials said.

On the eastern edge of Gaza City, Israeli forces flattened two Palestinian police outposts, Palestinian security sources said. At least a half-dozen Israeli helicopters hovered near Arafat's headquarters in Gaza City but eventually left without firing.

The Israeli operations in Gaza appeared to be in keeping with previous incursions. In those instances, the Israelis destroyed Palestinian security offices, and then pulled out after only a few hours.

The Israeli military said the incursion was a response to the attack on its military post Saturday.

The Israelis say they hold Arafat and his security forces responsible for the attacks against Israeli targets. They say that Arafat has failed to rein in Palestinian militants, and that members of the security forces have participated in shootings.

On Saturday night, two Israeli men and an Israeli woman were killed and two children were wounded when their car was ambushed by gunmen on a road just north of Jerusalem, near the West Bank settlement of Modiin, the Israeli army said.

The Al Aqsa Martyrs Brigade, made up of militants linked to Arafat's Fatah movement, claimed responsibility.

Saturday's violence began before dawn with one of the boldest and deadliest raids against Israeli forces.

Two Palestinian militants from the radical Democratic Front for the Liberation of Palestine climbed into the isolated Marganit military base in southern Gaza, killing three soldiers and wounding seven before they were shot dead.

Palestinian militants have targeted Israeli troops and Jewish settlers in Gaza throughout the current conflict. However, in most cases, the militants have fired from a distance or attempted roadside ambushes.

Saturday's direct assault on the fortified Israeli position appeared to catch the soldiers off guard.

The two attackers climbed over separate embankments in the dark, and both began shooting and throwing grenades at soldiers, the Israeli army said.

Soldiers shot back, killing one Palestinian at the base. The second man managed to flee, but was pursued and shot dead about four hours later while attempting to take cover at a greenhouse in a nearby Jewish settlement, the army said.

"It was a face-to-face battle and a very complicated battle," Israeli Maj. Gen. Doron Almog said of the shootout at the base.

The Democratic Front for the Liberation of Palestine said the assault was in retaliation for Israeli attacks on Palestinians. The group's leader, Nayef Hawatmeh, has been based in Damascus, Syria, for years, and the movement had not previously played a major role in the current Mideast fighting.

In a videotape made before the attack, the two Palestinian militants were shown with Kalashnikov rifles seated in front of a Palestinian flag.

"I donate myself to God and our people," said Hisham Abu Jamus, 24. Abu Jamus and the other assailant, Amin Abu Hatab, 26, previously worked for the Palestinian security forces, but quit after the Palestinian uprising began last September, Palestinian security sources said.

The Israeli troops in Gaza protect about 6,000 Jewish settlers who live in fortified enclaves surrounded by more than 1 million Palestinians.

The Palestinians want Gaza for a future Palestinian state, and have demanded that the Israeli troops and settlers leave the territory.