Palestinian security forces arrested more than 250 Hamas members in an overnight sweep throughout the West Bank after the Islamic militant group claimed responsibility foron the eve of .
With the Wednesday arrests, the government ofappeared to be trying to send a stern message to both its Hamas rivals and to Israel that it is committed to the new peace talks. Hamas condemned the crackdown as "treason."
In Washington, Israeli Prime Minister Benjamin Netanyahu said late Tuesday he would not let the shooting derail the negotiations.
Israel and the Palestinians are in Washington to begin talks aimed at creating an independent Palestinian state alongside Israel. The talks are to focus on core issues of the conflict, including the status of east Jerusalem, which the Palestinians want as capital of their future state.
In a possible hint on the Israeli position on Jerusalem, Israeli Defense Minister Ehud Barak indicated in a newspaper interview Wednesday that Israel would be willing to reach a compromise on the status of the city.
"West Jerusalem and 12 Jewish neighborhoods that are home to 200,000 residents will be ours. The Arab neighborhoods in which close to a quarter million Palestinians live will be theirs," Barak told the Israeli daily Haaretz.
He said "a special regime" would be needed around the Old City - home to sensitive Jewish, Christian and Muslim holy sites.
Barak's office confirmed the remarks were accurate, but would not say whether he expressed his personal views or official government policy. There was no immediate reaction from Netanyahu, who has said he would never agree to divide Jerusalem.
The Tuesday shooting immediately cast a shadow over President Barack Obama's push for Mideast peace, which was set to formally kick off later Wednesday with a White House dinner. It will be the first direct talks between Israeli and Palestinian leaders in nearly two years.
It also was a vivid reminder that while Hamas is locked out of the peace efforts, it remains a key player in determining the outcome of negotiations. The Iranian-backed group rules the Gaza Strip, one half of the territory claimed by the Palestinians for a future state, and has the power to sabotage negotiations at any moment.
During a visit to a West Bank army base Barak said the military "will do everything possible to quickly bring the perpetrators to justice." But he urged residents to show restraint.
A Palestinian security official, speaking on condition of anonymity under official guidelines, confirmed a crackdown was under way, but gave few details. He said the assailants from the shooting had not been found.
Hamas lawmaker Omar Abdel-Razek said some 250 low and midlevel activists had been rounded up by midday - the biggest single day sweep by Palestinian security in years.
"It's unprecedented," he said. "It is an act of treason."
Abbas, a Western-backed moderate, has carried out frequent crackdowns on Hamas since the Iranian-backed group defeated his forces and overtook Gaza three years ago. In turn, Hamas has frequently targeted members of Abbas' Fatah movement in Gaza.
Tuesday's attack occurred near Hebron, when a gunman opened fire on a passing vehicle, killing all four passengers inside - two men and two women from settlements in the area. The dead included a married couple with five children.
On Wednesday, hundreds of mourners attended a funeral in Beit Haggai, a settlement near Hebron where two of the victims lived.
Hebron has been a frequent flashpoint of violence in the past. Some 500 ultranationalist Jewish settlers live in heavily fortified enclaves in the city, surrounded by more than 100,000 Palestinians.
Hamas, which refuses to recognize Israel's right to exist and has condemned the new peace talks, quickly took responsibility for the shooting and vowed that more attacks would follow. About 3,000 Palestinians joined a rally in Gaza to celebrate the attack.
The shooting occurred shortly before Netanyahu landed in Washington, where he told reporters that he would not let the violence disrupt the peace efforts. "We will not let terror decide where Israelis live or the configuration of our final borders," he said.
Netanyahu has said protecting Israeli security would be his top priority as he negotiates the contours of a future Palestinian state with Abbas.
The shooting drew strong condemnations from Abbas' prime minister, Salam Fayyad, who accused Hamas of hurting the Palestinian dream of independence, the European Union and the United States.
The violence also added to Netanyahu's domestic troubles.
As leader of a hardline coalition dominated by ultranationalist and religious parties, Netanyahu is under heavy internal pressure to resume construction in West Bank settlements when a freeze expires on Sept. 26.
Netanyahu imposed the 10-month freeze last November to lure the Palestinians to the negotiating table. Settlers and their supporters in the government want an immediate resumption in construction, but the Palestinians have threatened to walk out of negotiations if building resumes.
Netanyahu has not said what he will do.
Following Tuesday's shooting, the Yesha Council, which represents the settlers, said it would unilaterally resume construction in West Bank settlements on Wednesday evening.
"The Palestinian leadership speaks softly in English while in Arabic it kills," said Yesha director Naftali Bennett. He said the settlements protect "the entire West from the onslaught of radical Islam."
It's not clear how much the settlers can realistically build. Police refused to say how they would respond.
The future of the settlements is one of the thorniest issues in the negotiations.
Some 300,000 Israelis now live in West Bank settlements, along with nearly 200,000 others in east Jerusalem. The Palestinians claim both areas, captured by Israel in the 1967 Mideast war, for their future state.