Prime Minister Benjamin Netanyahu pinned blame on the Palestinian leadership after a deadly attack on an Israeli police officer near the flashpoint West Bank city of Hebron.
"This assassination is the result of the incitement to hatred by Palestinian Authority (PA) leaders who continue to peddle hate-filled material against Israel," Netanyahu charged on Tuesday.
He said that this attitude had led to the murder of "a father driving home to celebrate a Passover dinner" on Monday, and deplored the lack of condemnation of the attack by the PA.
Israeli police said Tuesday the policeman killed was Baruch Mizrahi, a 47-year-old father of five who was a high-ranking officer in the intelligence division.
Israeli troops scoured a village near Hebron on Tuesday, a day after a gunman killed Mizrahi in the area.
The killing at the start of the Jewish Passover holiday was the first deadly attack this year on an Israeli in the occupied West Bank.
It came at a time of high tensions over the near-breakdown of US-brokered peace talks between Israel and the Palestinians.
The army searched several houses and businesses close to the scene of the killing southwest of Idhna, a village outside Hebron, residents told AFP.
They said soldiers roughed them up while searching homes, and added that army checkpoints set up around Idhna were still in place.
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The army said it was "conducting widespread searches for the perpetrators" of the attack.
Mizrahi's wife was seriously wounded and a nine-year-old child also hurt. Three other children were in the vehicle, according to Israeli military radio.
Israelis in another car said they saw a man wearing a helmet and firing a Kalashnikov assault rifle on the side of the road.
Army spokesman Peter Lerner said it was unclear if the attack was carried out by a single shooter or with accomplices, or if it was the work of a "local terrorist organisation."
The Palestinian movement Hamas that rules Gaza and a smaller Islamist group, Islamic Jihad, praised the attack.
It linked the assault to unrest in the flashpoint Al-Aqsa mosque compound in Jerusalem, where five Palestinians were arrested by Israeli police on Sunday.
But neither group claimed responsibility.
Hamas prime minister Ismail Haniya called for "Palestinian resistance in all its forms" against Israel at a news conference, in which he also praised the shooting and urged the kidnapping of Israeli soldiers.
The city of Hebron is home to nearly 200,000 Palestinians. Around 80 settler homes in central Hebron, housing about 700 Jews, live under Israeli army protection.