KARMEI TZUR, West Bank - Yael Sorek and her husband, Ayal, probably heard the gunfire from within their drab trailer on the outskirts of this Jewish settlement in the West Bank. Despite the dead-of-night darkness, they went to the door, still in their pajamas.

Two Palestinian intruders gunned them down, spraying their mobile home with bullets. Seconds later, an Israeli army patrol roared onto the scene. In a 10-minute gunbattle, the soldiers killed one of the Palestinians, and the other fled.

One soldier was killed in addition to the Soreks: Yael, 24, who was in the late stages of pregnancy, and Ayal, 23, an off-duty soldier from an elite infantry unit. Two other settlers and five soldiers were wounded.

The attack at Karmei Tzur early yesterday was the latest in a string of deadly raids on Jewish settlements in the West Bank and Gaza Strip carried out by Palestinians who want to eject Israelis from the territory.

The Soreks lived in one of 10 trailers scattered down a slope 200 yards from the fence that surrounds Karmei Tzur. Its establishment is part of a plan to expand Jewish settlement in the West Bank, despite U.S. and other international calls for an end to the colonization.

Also yesterday, the Israeli navy said it intercepted two armed Palestinians swimming in the Mediterranean toward the Dugit settlement in the Gaza Strip, killing at least one of them, and three Palestinians were killed in an explosion near another Gaza settlement.

And late last night, at least two Palestinian gunmen tried to infiltrate the Yitzhar settlement near the West Bank city of Nablus. One or two of them were killed, and four Israeli soldiers were wounded, the army said.

The attacks came as Israeli Prime Minister Ariel Sharon prepared to leave for meetings in Washington with President Bush. Sharon's office condemned the attacks and blamed them on Palestinian Authority President Yasser Arafat and his inability to stop violence.

'Hard to secure'

The cluster of trailers attacked early yesterday was placed outside Karmei Tzur in February last year, the army said, and was named for Shmuel Gillis, a doctor from the settlement who was killed at that time in a Palestinian ambush.

"It's hard to secure these settlements, but it's not impossible," said Brig. Gen. Amos Ben-Avraham, the Israeli army division commander for the region. "Sometimes we succeed, and sometimes we don't."

The mobile homes were deserted yesterday at midday. The one where the Soreks had lived was roped off with police tape.

Because yesterday was the Jewish Sabbath, no one from the staunchly religious settlement would speak to reporters.

Ben-Avraham, the army commander, said two Palestinian assailants apparently crossed a sparsely vegetated valley from the south and slipped into the Karmei Tzur outskirts about 2:30 a.m. No fence protected the trailers, and an army watchtower that guards them is staffed only during the day.

An army patrol noticed the two intruders, however, and was rushing toward them when they opened fire, Ben-Avraham said. One Palestinian armed with an M-16 and a knife is apparently the one who killed the Soreks, while the second assailant, armed with a Kalashnikov, escaped.

Time to reload

The gunfight lasted long enough for both Palestinians to repeatedly change magazines, firing off a couple hundred rounds, Ben-Avraham said.

Ben-Avraham said the Soreks must have come to the door when they heard the gunfire. Their bodies were found at the doorway, he said.

Tracy Wilkinson is a reporter for the Los Angeles Times, a Tribune Publishing newspaper.