Even in a country long accustomed to violence, the grisly details of the killings late Friday stunned Israel. Among the victims were a 4-year-old boy and his baby sister. Their pictures leaped from Israel's front pages, pushing news of the Japanese earthquake and tsunami disaster aside.
As Israel's military searched for the Palestinian suspects in a broad sweep in the West Bank, thousands of mourners thronged a Jerusalem cemetery for the funeral.
"There is not a Jewish heart that is not shedding a tear," Chief Rabbi Yona Metzger said in a eulogy, his voice cracking in anguish. "After such horrific pictures, with whom do we have to sit and talk peace?"
Mourners screamed and wailed as the bodies of the three male victims were brought in wrapped in white and black prayer shawls, the two females in blue shrouds.
Many rocked back and forth in prayer as speakers addressed the audience, and family members collapsed in grief.
The bloodshed, which shattered a lengthy lull in the West Bank, threatened to drive Israeli-Palestinian peacemaking further out of reach. Peace talks have been stalled since September, and the combination of deadly violence against Israelis and new settlement construction was likely to deepen the mutual distrust.
Officials said assailants cut through a fence surrounding the settlement of Itamar, entered the home of the Fogel family, and killed the parents -- Udi, 36, and Ruth, 35, -- and three of their children, Yoav, 11, Elad, 4, and 3-month-old Hadas.
An older daughter who was out with friends came home and discovered the carnage. The attack took place shortly after the family finished the weekly dinner celebrating the Jewish Sabbath.
Footage of the gory scene broadcast on Israeli media showed children's toys in pools of blood and tipped-over furniture.
Israel indirectly blamed the Palestinian government for the carnage.
Israel long has contended that Palestinian textbooks and official media are full of hatred toward the Jewish state, and that killers of Israelis are often glorified.
Sunday, a group of activists from Palestinian President Mahmoud Abbas' Fatah movement dedicated a square in the West Bank city of Ramallah to Dalal Mughrabi, a female militant who carried out a 1978 bus attack that killed 37 Israelis. Aides to Mr. Abbas said they tried to stop the ceremony and the move was not officially sanctioned.
Addressing his Cabinet, Israeli Prime Minister Benjamin Netanyahu said Mr. Abbas called him to express sorrow over the violence.
"I told him that we expect much more unequivocal condemnations, but even more than that, we want to see unequivocal action by the Palestinians to stop allowing this incitement," he said. "We think that educating people toward peace is an integral part of peace."
Israeli troops continued with a second day of raids in Palestinian villages around Itamar, which has poor relations with its Arab neighbors. Officials said some 20 suspects were in custody, though there was no word on whether any were believed to be the killers.
In a slap at the Palestinians, Israel announced that a special team of Cabinet ministers led by Mr. Netanyahu approved the construction of up to 500 homes in Jewish settlements.
Jewish settlements are at the heart of the impasse in peace efforts. The Palestinians refuse to negotiate as long as Israel expands the enclaves, which are built on occupied territories claimed by the Palestinians.
The U.N.'s Mideast envoy, Robert Serry, criticized the new construction as counterproductive.