RAMALLAH, West Bank ? Israeli troops rounded up hundreds of Palestinian men for questioning, battled gunmen and imposed a curfew Saturday in the West Bank’s main city. Yasser Arafat was penned up in his office, surrounded by Israeli troops and trying to keep up his staff’s morale, aides and witnesses said.

Israel’s military offensive, launched Friday to hunt down militants after a series of Palestinian attacks, will last as long as it takes “to guarantee the safety of our homes,” Defense Minister Binyamin Ben-Eliezer told Israeli television. Eleven Palestinians and two Israelis have been killed in the two days of fighting in Ramallah.

In a new attack, a suicide bomber blew himself up in a crowded cafe in Tel Aviv’s entertainment district Saturday evening, killing himself and wounding at least 32 people.

Two other Palestinians heading into Israel to conduct a suicide attack got into a gunbattle with Israeli police at the edge of the West Bank. An Israeli officer and the two Palestinians were killed.

President Bush said Saturday that he respected Israel’s right to defend itself and demanded that Arafat do more to stem violence.

“I can understand why the Israeli government takes the actions they take. Their country is under attack,” Bush said. He said Arafat “can do a lot more” to prevent terrorist attacks.

“He’s got a lot of people that listen to him still,” Bush said. “He’s got to make it absolutely clear that the Palestinian Authority does not support these terrorist activities.”

The Palestinian news agency responded harshly, criticizing U.S. envoy Anthony Zinni and warning Arab leaders they could be overthrown for failing to back the Palestinians.

Wafa said Arafat “shocked the invader” by refusing to surrender, and complained that the United States and Arab leaders were harming the Palestinian cause.

U.S. supports Israeli withdrawal

Despite the harsh U.S. words for the Palestinians, Washington supported a U.N. Security Council resolution passed early Saturday that called on Israel to withdraw from Palestinian cities, including Ramallah.

European nations criticized Israel, calling on it to implement the resolution, while angry protests broke out in several Arab nations.

At the same time, Israel’s tense northern border with Lebanon flared up. Hezbollah guerrillas fired rockets and mortar shells at Israeli outposts in a disputed border area, and Israeli warplanes responded with strikes on suspected Hezbollah positions in south Lebanon.

Israel is expected to broaden its offensive in Palestinian-controlled areas in coming days, and the military was in action on two other fronts Saturday.

Tanks moving in

Tanks rumbled into the Palestinian town of Beit Jalla, just south of Jerusalem and next to Bethlehem, where Christians are observing Easter weekend. Tanks also entered the town of Beituniya, outside Ramallah, surrounding the military compound of West Bank security chief Jibril Rajoub. He said his men would resist an Israeli takeover.

In other military measures, Israeli forces entered Seida, a village near Jenin in the West Bank and killed two Palestinians, one of them an Islamic Jihad activist, villagers said. The Israeli military said Israeli soldiers returned fire from a building, killing two gunmen, and Israeli soldiers left the village after the operation.

Israeli tanks moved into the Palestinian town of Beit Jalla after gunmen there fired guns and a mortar shell at a Jewish neighborhood in a disputed part of Jerusalem claimed by both sides. Also, Israeli armored vehicles entered a Palestinian neighborhood of the city of Hebron after gunmen fired at houses in a Jewish enclave below, witnesses said.

In response to the U.N. resolution, Israel said it was forced to take military action “because the Palestinians are launching terrorism against our citizens.”

Israeli troops took over the streets in Ramallah and seized the buildings in Arafat’s complex Friday, but remained just outside Arafat’s office.

In a phone call to Arafat, Secretary of State Colin Powell blamed Palestinian attacks for scuttling peace efforts.