Associated Press Israeli soldiers on top of an armored personnel carrier start up the vehicle to move into the northern West Bank town of Tulkarm yesterday. The Israeli army stepped up their West Bank offensive, which they are calling "Operation Protective Wall," with incursions into the the northern Palestinian towns of Jenin and Salfit.

BETHLEHEM, West Bank - Israeli tanks rolled into Nablus yesterday and battled Palestinian gunmen at street barricades, taking Israel's offensive into the West Bank's largest city. In Bethlehem, troops encircled scores of Palestinians inside one of Christianity's holiest shrines - the Church of the Nativity.

Shellfire thundered as Israeli tanks entered Nablus, witnesses said. About 300 to 400 tanks surrounded the city of more than 100,000 people, where Palestinian gunmen and police roamed the streets, closing roads with sand bags and planting homemade mines.

Earlier yesterday, Israeli forces took over the Palestinian towns of Jenin and Salfit and surrounded the Jenin refugee camp, a militant stronghold. Israeli tanks and helicopter gunships exchanged fire with hundreds of armed men in the camp. Three militiamen, a nurse and a 13-year-old boy were killed in the fighting, militia leaders said.

Israel's West Bank offensive - dubbed "Operation Protective Wall" - seeks to crush Palestinian militias after a wave of terror attacks against Israelis. Israeli forces have entered six major Palestinian towns and several villages since Friday.

In Bethlehem, Israel and the Palestinians remained locked in a standoff over scores of Palestinian police and militiamen as well as priests, nuns and civilians holed up in the Church of the Nativity, built over the area where tradition says Jesus was born. The armed men had forced their way into the shrine Tuesday, after hours of intense fighting with Israeli forces.

The Palestinians rested in pews and on the stone floor. Samir, a Palestinian policeman, denied Israeli charges that shots were fired from the church. "Most of the guys have run out of bullets and secondly, we're completely surrounded," said Samir, who would not give his last name.

The Israeli army spokesman, Brig. Gen. Ron Kitrey, said Israel would not use force to drive out the gunmen but would not let them go free. Raanan Gissin, an adviser to Israeli Prime Minister Ariel Sharon, said the gunmen "abuse churches ... as a place from which they can conduct their attacks on our forces." Israel says its forces are under orders not to harm holy places.

Israel ignored requests to deliver food and medicine to the church, where about 200 people were trapped, the Palestinian governor of Bethlehem, Mohammed Madani, said. Ten of the gunmen were wounded, including one who was in critical condition, Madani said.

Tanks were stationed at the edge of Manger Square, where the church is located, and troops occupied the municipality building overlooking the square, Bethlehem Mayor Hana Nasser and other witnesses said.

The bodies of four gunmen shot dead in a firefight Tuesday remained sprawled on a side-street near the church, with rescue services unable to reach them because of constant shooting. Two more bodies were found later yesterday, one in a mosque and one in a church. U.S. officials escorted some 20 foreigners, including Americans and Britons, out of Bethlehem in an armored convoy.

President Bush repeated his support yesterday for Israel's offensive. "In the wake of the suicide bombings and the attacks that took place in Israel, he understands and respects Israel's right to defend herself," White House spokesman Ari Fleischer said.

But with the assault expanding, daily protests in Arab nations have grown more violent. Thousands of Lebanese and Palestinians clashed with security forces yesterday outside the U.S. Embassy in Beirut, with at least 25 reported injured as protesters threw stones and security forces used tear gas and water cannons.

Under pressure to cut off ties completely with Israel, Egypt took a more limited step yesterday, announcing it would suspend all diplomatic contacts with Israel except those aimed at helping the Palestinians.

At least 30 Israeli tanks rumbled into the northern West Bank town of Jenin from all sides, exchanging fire with Palestinians at the entrance of a nearby refugee camp. Israeli forces took over several tall buildings that provided views into the camp.

Among those killed in the camp were a 27-year-old nurse and Ziad Amer, local leader of the Al-Aqsa Martyrs' Brigade, a militia linked to Palestinian leader Yasser Arafat's Fatah group. "We will not surrender," Amer said in a phone interview just before his death. "We will fight until victory or death."

In the West Bank commercial center of Ramallah, Arafat remained pinned down by Israeli troops and tanks, his compound now ringed by barbed wire.

By yesterday morning, more than 800 Palestinians - men ranging from their mid-teens to their mid-40s - had been rounded up in Ramallah on suspicion of being militants. The Palestinians denounce the mass roundups as collective punishment, but Israel says they are a legitimate means of hunting down wanted men.

Arafat rejected a proposal by Sharon on Tuesday that diplomats fly the Palestinian leader into exile, saying he would rather be a "martyr" than leave. "Is it his (Sharon's) homeland or ours?" Arafat asked the Arab satellite TV station Al-Jazeera.

Israel TV on Tuesday showed footage of military chief Lt. Gen. Shaul Mofaz urging Sharon to expel Arafat.

During a joint visit to an army base in the West Bank, Mofaz was seen telling Sharon: "We should kick him out." Sharon - apparently unaware his comments were being recorded - replied, "I know." Mofaz continued: "This is an opportunity now that won't return."

Spanish Prime Minister Jose Maria Aznar, chairman of the rotating EU presidency, asked Sharon to allow contact between Arafat and international leaders. Aznar tried to talk by phone four times with Arafat on Sunday but each time the line went dead, the Madrid daily El Mundo reported. The paper said that when Aznar sought an explanation from Sharon he was told: "Mr. Aznar, you are trying to talk to the chief of the terrorists."

In Amman, Dr. Ashraf al-Kurdi, a leading Jordanian neurologist who regularly examines Arafat, said yesterday that the 72-year-old Palestinian leader's checkup is four months overdue, but that Arafat was "in good spirits" when the two spoke Sunday.

Arafat has noticeable tremors in his lower lip, which doctors call a nervous tic, though they raised speculation he suffers from Parkinson's disease, a degenerative neurological disease.

Gissin, the Sharon adviser, said the international community was too concerned about Arafat and should recognize Israeli suffering; dozens of Israelis have been killed in suicide bombings in the past week, including 25 in an attack on diners attending a Passover meal.

"I think we should all be reminded that last night we buried the 25th victim of the Passover massacre," Gissin said.

Late Tuesday, Israeli soldiers foiled a suicide bombing on the edge of the West Bank by shooting at explosives strapped to the attacker's chest, detonating the bomb and killing the man. The bombing was the seventh such attack in about a week.