A second Palestinian suicide bombing in two days killed three Israelis on Thursday, wounded more than 60 people and abruptly disrupted peace talks between Israelis and Palestinians.
The attack on a downtown Jerusalem street raised a serious threat to efforts by U.S. special envoy Anthony Zinni to forge a cease-fire and end months of trauma and violence.
Palestinian leader Yasser Arafat quickly condemned the bombing of Israeli civilians.
"We will take immediate and required steps to put an end to these actions and those who stand behind them," Arafat said from his West Bank headquarters in Ramallah, soberly reading a statement for broadcast. "We will spare no effort in doing so. We will continue with our efforts to make the mission of General Zinni succeed."
But Zinni and other officials were blunt in their criticism of Arafat, blaming him for a lack of will in preventing assaults even by groups with links to his own Fatah movement.
Palestinian officials said Secretary of State Colin Powell had telephoned Arafat, rebuked him for the attack and demanded punishment for those responsible.
"(Zinni) regrets that Chairman Arafat and the Palestinian Authority have not taken any steps or exerted any effort to prevent this or any other attacks and to deal with those who are responsible," according to a statement released by the U.S. Embassy in Tel Aviv. Efforts toward a cease-fire would succeed, the statement said, only if Arafat "exerted such efforts immediately and unequivocally."
The State Department later said Powell had added the al-Aqsa Martyrs Brigades, which claimed responsibility for Thursday's bombing, to its list of designated foreign terrorist organizations. Al-Aqsa, a shadowy faction linked to Arafat's Fatah Revolutionary Council, has claimed responsibility for dozens of attacks on Israeli soldiers and civilians over the last several weeks.
Al-Aqsa is the first Palestinian organization to be added to the official terrorist list since the latest round of Israeli-Palestinian fighting began in September 2000.
Israel canceled a round of talks with Zinni and Palestinian leaders shortly after the explosion sheared through King George Street, just outside a French pastry shop as the evening rush hour began.
Israeli Prime Minister Ariel Sharon met with his security Cabinet late into the night. It was unclear whether other planned talks would be affected.
"I just saw a man explode. I saw his head cut off," said Israel Apter, an employee at a nearby printing shop. "I saw fresh-cut hands on the street, I saw people gushing blood. I was scared out of my wits."
On Wednesday, a suicide bomber ripped apart a bus near Afula, in northern Israel, killing seven people in the single deadliest terror attack since Zinni arrived a week ago.
Thursday's bombing unsettled hopes for a quick announcement of a truce to end the 18-month intifada, as the Palestinian uprising is known. Since his arrival, Zinni had voiced optimism about the prospects for some kind of agreement between Israel and the Palestinians. This week, Zinni had urged Vice President Dick Cheney, in a quick visit to the region, to make a gesture to Arafat to motivate him to move closer to a peace proposal initiated months ago by CIA director George Tenet.
Cheney had promised to meet with Arafat, an unprecedented step, if the Palestinian leader would agree to a cease-fire and ensure a cessation of terror attacks.
According to diplomatic officials cited by the Chicago Tribune, on Thursday morning the Americans were anticipating a breakthrough by the weekend. Plans were in place for Cheney to return to Jerusalem as early as Saturday night to meet with Sharon and then quickly move Sunday or Monday on to Cairo to meet with Arafat.
Then Arafat, who had been under virtual house arrest by the Israelis for months because of the escalating violence, would have been able to travel from Cairo to Beirut for an Arab League conference, where Saudi Arabia is expected to present an Arab peace proposal.
By Thursday night, all hopes in Arafat were in question. The blast undermined Arafat's bargaining position, by any measure, and analysts here were struggling to explain the continuation of terror at this most delicate time of negotiation.
Senior Israeli security officials, according to the Chicago Tribune, had raised concerns that Palestinian groups were increasingly emboldened by the success of their attacks and gaining confidence in wielding power.
Those officials said a younger generation has been clearly jockeying for political power in Arafat's Fatah movement. Al-Aqsa, one military faction, has raised its profile with dozens of attacks that have been some of the most brutal in the current uprising. Al-Aqsa has been described as loyal to Arafat, but longtime observers here see its attacks as largely self-directed and often at odds with Arafat's stated policy against suicide bombings.
Arafat, who revels in playing people off each other in his leadership role, has been slow to address the semi-independent faction or to enforce discipline in al-Aqsa and other Fatah factions. Increasingly, security officials told the Chicago Tribune, there is fear that Arafat has lost some ability to do so.
It was anyone's guess Thursday night what or whether Arafat knew in advance about al-Aqsa's latest bloody endeavor.
Al-Aqsa identified the suicide bomber as Mohammed Hashaika, 22, who was from a West Bank village near the city of Nablus. Palestinian officials said that Hashaika had lost two relatives to an Israeli missile attack last year.
Thursday night, Israeli intelligence officials were quoted on national television as naming Hashaika as a terrorist targeted for arrest by Israel. Palestinian police had arrested Hashaika a few weeks ago, it was reported, but did not jail him as the Israeli government had demanded.
_ Information from the Los Angeles Times was used in this report.