Karmei Tsur, West Bank ? Palestinian gunmen sprayed bullets through a cluster of mobile homes as the Jewish settlers inside were sleeping Saturday, killing three people including a pregnant woman and her husband.

One attacker was killed and a second escaped. Israeli troops in armored vehicles entered a nearby Palestinian town as helicopters trained spotlights on the area in a pre-dawn search for the gunman.

In the Gaza Strip, three Palestinians were killed in two attempted attacks on Israelis. One was an armed man who was swimming toward a Jewish settlement on the Mediterranean Sea, the Israeli army said.

The violence came as Israeli Prime Minister Ariel Sharon prepared to leave for Washington, where he is to meet Monday with President Bush.

The attack on Karmei Tsur, a settlement of about 100 families in the southern West Bank, began shortly after 2 a.m., when two gunmen opened fire on a cluster of about 15 mobile homes separated from the rest of the settlement.

A security guard killed one of the gunmen minutes later at the door of a trailer, the army said. The attacker was holding a grenade.

After daybreak, reporters could see soldiers carrying a stretcher with a body wrapped in a white blanket. Another body lay covered by a red blanket. One trailer door was punctured by bullets, and blood was smeared on the wall nearby.

The gunmen killed a young man and his wife, who was pregnant, settlement spokeswoman Esty Uliel said. A wounded man died later, military sources said. Three other Israelis were injured.

Uliel barred reporters from speaking to residents Saturday, citing the sanctity of the Jewish Sabbath.

The trailers, which are protected but not completely surrounded by a barbed wire fence, are for newcomers waiting for permanent housing. The neighborhood of mobile homes was named after Dr. Shmuel Gilles, a Karmei Tsur resident who was killed in a Palestinian attack on his car last year.

There was no immediate claim of responsibility and no comment Saturday from the Palestinian Authority, which Israel has held responsible for continuing attacks.

“Once again we are witnessing an act of terrorism being launched from the Palestinian territories, as a result of the Palestinian Authority’s refusal to take action against terrorism,” the military said in a statement.

But Palestinian leader Yasser Arafat’s spokesman, Nabil Abu Rdeneh, said, “the Israelis should blame themselves, they failed at the political level and at the security level as well.”

“They have to understand that they should live peacefully with the Palestinian people with its elected leadership, otherwise their security and our security will be in danger,” he said.

In the Gaza Strip, Israeli troops fired at two Palestinians swimming toward the Jewish settlement of Dugit, and one body later washed ashore, the military said. It said the Palestinian had a grenade, an assault rifle and ammunition.

Officials at Shifa Hospital in Gaza City identified the body as that of Sayed al-Tatar, 30, a member of the militant group Islamic Jihad who also worked in the Agriculture Ministry.

Also Saturday, an explosion went off along the fence between Gaza and Israel, and troops found the bodies of two Palestinians, the army said.

In recent months, there has been an increase in attacks on Jewish settlements by Palestinian gunmen. In a shooting attack May 28, three Israeli teen-agers were killed while playing basketball in the Itamar settlement near Nablus.

In Washington, Bush was to consult this weekend with Mideast leaders, including Egyptian President Mubarak, before revealing his plan for putting peace negotiations back on track.

While Mubarak is expected to appeal for a firm timetable for establishing a Palestinian state, Sharon will try to persuade Bush not to commit to dates, a Sharon adviser said on condition of anonymity. Sharon will also tell Bush that he will not negotiate a peace deal until Palestinian attacks on Israelis stop, the adviser said.

On Friday, Arafat accused Israel of waging a “dirty war” against the Palestinians. In 21 months of fighting, Israel’s military has repeatedly raided Palestinian areas and carried out large-scale sweeps in response to attacks by Palestinian militants.

Israeli troops enforced a curfew Saturday on Jenin, the West Bank hometown of a Palestinian suicide bomber who attacked an Israeli bus earlier in the week, killing 17 passengers. About 30,000 residents of Jenin were confined to their homes by the curfew.