U.S. Secretary of State Hillary Clinton said Saturday that she was shocked and deeply saddened by the killing of five Israeli family members in the West Bank.

"To kill three innocent children and their parents while they sleep is an inhuman crime for which there can be no justification," said Clinton. "The murderers must be found and brought to justice."

Earlier Saturday, the United States called the killing a terrorist attack.

"We call on the Palestinian Authority to unequivocally condemn this terrorist attack and for the perpetrators of this heinous crime to be held accountable," the White House said in a statement.

Palestinian Prime Minister Salam Fayyad said Saturday in response to the attack, "Violence does not justify violence, we condemn it completely, whoever does it and whoever the victims are," Fayyad told the Associated Press.

British Foreign Secretary William Hague also denounced the attack in Itamar, calling it "an act of incomprehensible cruelty which I utterly condemn."

Five members of an Israeli family – two parents and three of their children – were killed Friday night when a terrorist broke into their home in the settlement of Itamar, near the West Bank city of Nablus, and stabbed them all to death.

"We tell the criminals of the occupation that their crimes won't pass without punishment," the movement concluded.