The war between Israel and the Palestinians invaded the birthplace of Jesus Christ Tuesday, as dozens of armed Palestinians holed up inside the Church of the Nativity in Bethlehem.

Meanwhile, Israeli tanks rolled into two West Bank towns before dawn Wednesday, exchanging fire with Palestinian fighters, witnesses said. The Israeli moves into Salfeet and Jenin, a northern town that has been home to some of the suicide bombers who have been terrorizing Israelis, came a day after Israel seized control of Bethlehem and another West Bank town.

Amid the fiercest Israeli offensive in 18 months of conflict, Palestinian leader Yasser Arafat angrily rejected an Israeli offer to free him from confinement in his compound in the West Bank town of Ramallah — provided he goes into exile. Arafat spent a fifth straight day pinned down by Israeli troops and tanks, his compound now ringed by barbed wire.

Holy places were not immune from violence that raged the length and breadth of the West Bank. Dozens of armed Palestinians were holed up inside the Church of the Nativity in Bethlehem, which is built over the grotto where tradition says Jesus was born. About 20 of the gunmen were wounded and being tended to by nuns, according to witnesses trapped in the church compound.

The armed men, some of them Palestinian policemen, forced their way into the church after running battles with Israeli troops firing from helicopter gunships and from tank-mounted machine guns. At nightfall, the bodies of four gunmen lay sprawled just off Manger Square, where the church is located.

As Israeli troops circled the church, the men rested in pews and on the stone floor, said Samir, a Palestinian policeman inside the church. About 20 of the gunmen were wounded and being tended to by several nuns and priests, Samir said.

"Most of the guys have run out of bullets," Samir said by telephone.

About 120 armed men were hiding in the church, said Marc Innaro, a correspondent for Italy's RAI TV, who was trapped in the compound by the fighting along with five colleagues.

Israel, meanwhile, was forced to turn its eyes to the north, warning Syria and Lebanon that there could be "very serious consequences" if Hezbollah forces do not withdraw quickly from what it says is a buildup of troops along its northern border.

"Israel has told a number of European countries, including Italy, that it is concerned about what appears to be a massing of Hezbollah forces on its northern border with Lebanon," a senior Italian foreign ministry official told the Reuters news agency in Rome.

"We have passed onto Syria and Lebanon that Israel says that if there is no disengagement, then the Israeli response could be very serious," he said.

Hezbollah has often hinted that it might engage the Israelis along the border with Lebanon, thus opening another front in Jerusalem's ongoing battle with the Palestinians, which already is taking place in the West Bank and Gaza Strip.

At least 30 tanks rumbled into Jenin from all sides, opening the sixth day of a crushing offensive designed to root out Palestinian terrorists. They exchanged heavy machine gun fire with Palestinians in the city and at the entrance of a refugee camp, witnesses said. A 27-year-old Palestinian woman was shot to death, Palestinian hospital officials said.

Tanks were taking up positions in Salfeet. Witness said the Israelis did not appear to be meeting with armed resistance there.

Israeli troops pressed ahead with house-to-house searches for Palestinian militants and weapons as part of what Israel calls "Operation Protective Wall" — aimed at halting terror attacks targeting Israelis.

In the seventh such attack in as many days, a Palestinian suicide bomber was blown up when Israeli soldiers shot and detonated explosives he had strapped to his body. The incident occurred at a checkpoint in Baka al-Sharkiyeh, a Palestinian village along the line between Israel and the West Bank. The man died but no one else was injured, the military said.

In a dramatic gesture that underscored hardships caused by the Israeli incursion, Palestinians buried 15 of their dead in a hospital parking lot in Ramallah. Families of the dead had been unable to claim the bodies, which were decomposing in a hospital morgue because power cuts made refrigeration impossible. Relatives wailed and gunfire from fighting echoed as the bodies were placed in common graves carved out by a bulldozer — one for 13 men, one for two women.

Ramallah residents, though, got a respite of a few hours from a curfew that has been in effect since Israeli tanks and troops moved in on Friday. People poured into the shops, lugging away canisters of cooking oil and plastic bags bulging with pita bread. Canned goods were popular, as many people have no electricity and perishable food has been rotting in refrigerators.

By nightfall, most of the about 400 Palestinians trapped in the compound of West Bank security chief Jibril Rajoub near Ramallah had surrendered to Israeli troops, in a deal brokered by U.S. and European officials. About eight men remained inside. The sprawling compound was battered by the Israeli onslaught, with gaping holes punched in rooftops and building facades by shellfire and rockets.

As the fighting intensified, Israeli Prime Minister Ariel Sharon proposed publicly for the first time that diplomats fly Arafat into exile. Sharon noted such a move would require Cabinet approval. Arafat denounced the suggestion, saying he would rather be a "martyr" than go into exile.

Israeli Foreign Minister Shimon Peres said the offensive would last three to four weeks, the first senior Israeli official to give a time frame. However, Sharon has said the campaign was open-ended.

In Washington, Secretary of State Colin Powell said Israel should end the campaign quickly, but suggested the United States would not insist on an immediate Israeli withdrawal. "I would guess it will take them [the Israelis] a couple of weeks" to conclude the mission, Powell said on NBC's Today show. Powell expressed opposition to expelling Arafat. "Until he decides he's going to leave the country, it seems we need to work with him where he is."

Powell also spoke to Jordanian Prime Minister Ali Abul-Ragheb, who told him that Israeli aggression was threatening the stability of the region, the Petra news agency said.

The State Department, citing a "deteriorating security situation," warned Americans to defer travel to Israel, the West Bank and Gaza and said dependents of American diplomats in Jerusalem were being encouraged to go home. Similar warnings to Americans to stay away from Israel were issued in December and January. Americans living in Jerusalem, the West Bank and in Gaza were advised to consider relocating.

Palestinian civilians have mainly tried to stay out of harm's way by huddling inside their homes, and the streets proved deadly dangerous again Tuesday. A 56-year-old Palestinian woman was fatally shot on her way home from Ramallah Hospital, apparently by an Israeli sniper, doctors said. She had gone to the hospital to have a plaster cast removed from her leg, they said.

There was also a heavy exchange of fire outside the Santa Maria Convent in Bethlehem run by the Salesians, a Roman Catholic order. Near the convent, 64-year-old Samieh Abdeh and her 38-year-old son Khaled were wounded by Israeli fire at their home, Abdeh's son Sami said. Israeli troops prevented ambulances from reaching the home, and the two bled to death, Sami Abdeh said.

Also Tuesday, three Israelis died of wounds sustained in last week's suicide bombing during a Passover banquet in an Israeli hotel. That brought the total number of victims to 25, making it the deadliest Palestinian attack in 18 months of fighting.

The Associated Press contributed to this report.