Palestinian leader Yasser Arafat is once again besieged in his compound in the West Bank city of Ramallah, with Israeli troops and tanks surrounding his offices and demanding the surrender of some senior Palestinian officials. Israeli snipers shot and killed one Palestinian police officer in the compound, and a second Palestinian man was reported wounded. The assault follows Thursday's suicide bombing in Tel Aviv, which killed six people and injured dozens more.

Plumes of dust and smoke swirled above Yasser Arafat's compound Friday morning, as Israeli forces blew up more buildings, including one used by the Palestinian leader's security guards. Much of the compound in central Ramallah is already in ruins, after several attacks and sieges by Israeli forces earlier this year.

Israel is demanding the surrender of about 20 Palestinian militants suspected of organizing attacks against Israel. Among them is senior Palestinian intelligence official Tawfik Tirawi. A number of Palestinians inside the compound have apparently turned themselves in, but Mr. Tirawi was not among them.

Yasser Arafat has remained inside his offices. His aides say he has been on the telephone, calling Arab and other world leaders, and asking them to pressure Israel to end its siege.

The Israeli assault on Mr. Arafat's compound began late Thursday, a few hours after a Palestinian suicide bomber blew himself up on a crowded bus in central Tel Aviv. A day earlier, another suicide bomber killed himself and an Israeli policeman in northern Israel, ending a six week lull in suicide attacks against Israel.

After the Tel Aviv bombing, the Israeli Cabinet met with Prime Minister Ariel Sharon, and decided to further isolate the Palestinian leader. On Friday, Defense Minister Binyamin Ben Eliezer told Israel's Army Radio, the aim is to keep up the pressure. He also said Israel has no intention of expelling or harming Mr. Arafat

Israeli forces also moved into several areas of the Gaza Strip overnight, blowing up workshops around Gaza City, which they said were used to make weapons. Two Palestinians were reported killed in the Gaza incursion. In addition, Israel has re-imposed strict curfews in most West Bank population centers.

The militant group Hamas, which is on the U.S. State Department's list of terrorist organizations, claimed responsibility for Thursday's attack. But Israeli officials quickly blamed Mr. Arafat for not preventing it. They have repeatedly accused him at doing nothing to rein in Palestinian militants. Palestinian officials say their own security forces can do little to deter attacks, since Israel has demolished most of the Palestinian Authority's infrastructure, and Israeli troops continue to occupy most Palestinian cities and towns.

Each side has consistently blamed the other for the violence, which has been going on, almost non-stop, for the past two years. More than 1,500 Palestinians and around 600 Israelis have been killed in that time.