JERUSALEM -- Israel cut off all contact with Yasser Arafat early Thursday after Palestinian militants killed 10 more Israelis in a bus ambush. The move could wreck U.S. efforts to construct a truce.
The Israeli Security Cabinet issued its dramatic announcement just hours after Arafat bowed to long-standing Israeli demands and ordered the offices of the militant Hamas and Islamic Jihad groups closed.
The cabinet statement said Arafat was "directly responsible" for the attacks "and therefore is no longer relevant to Israel, and Israel will no longer have any connection with him."
Justice Minister Meir Sheetrit said Israel had reached "the moment of truth" in its battle against terrorism. "We have been talking with the Palestinians at all levels for two years," Sheetrit said. "Now it is time for Israel to defend itself."
Israeli helicopters targeted Arafat's West Bank headquarters in Ramallah early Thursday, Palestinian security officials said, adding that Arafat left the building shortly before it was hit.
At a news conference with Sheetrit after the Cabinet meeting, Brig. Gen. Dan Harel, Israel's chief of military operations, said Arafat himself was not a target. The Cabinet said Israeli forces would be deployed around Palestinian towns to make arrests and confiscate weapons.
U.S. envoy Anthony Zinni was trying to establish two days of calm to rebuild trust. He has been in the region two weeks trying to arrange a truce to end more than 14 months of Palestinian-Israeli violence.
Sheetrit said there would be no more contact with Arafat or his Palestinian Authority and that meetings of security commanders, sponsored by Zinni, would cease.
Since Nov. 26, when Zinni arrived, 50 Palestinians and 44 Israelis have been killed in violence. The Palestinian toll includes 18 armed attackers and 10 suicide bombers.
Hamas said it was responsible for the bus attack just after nightfall Wednesday, which also injured 30. The crowded vehicle was ambushed as it climbed a winding road near the Jewish settlement of Emmanuel in the West Bank, 25 miles north of Jerusalem.
Wednesday's unrelenting violence started shortly after midnight with an Israeli helicopter strike that killed four Palestinian militiamen in response to mortar fire on Jewish settlements. Israeli warplanes struck back after the bus bombing, and Arafat ordered the offices of Hamas and Islamic Jihad closed.
Palestinian militants have ignored Arafat's calls for a cease-fire. Israel reserved the right to strike back at the Palestinian authority for attacks by the militants and dismissed as a sham Arafat's recent arrest of 180 militants.
Two bombs planted on the roadside exploded, immediately killing four bus passengers, said the regional police commander, Shahar Ayalon.
One or more gunmen then opened fire from surrounding hills.