A late-night attack on a northern Israeli kibbutz that killed five has created another obstacle for the new US peace mission to the region.
A mother and her two children, aged four and five, and two other adults were gunned down by a Palestinian who sprayed automatic rifle fire on the residents of Metzer after he managed to infiltrate the collective farm.
Another seven Israelis were injured in the shooting spree before the gunman escaped. As security forces continued a hunt in the area, newly appointed Defence Minister Mr Shaul Mofaz met aides to consider the inevitable reprisal.
"Israel is going to strike back hard to their murderous attack," a defence ministry official told army radio.
Palestinian leader Mr Yasser Arafat swiftly condemned the killings and also announced a committee had been set up to examine whether a splinter group from his own Fatah movement had carried out the attack to sabotage talks in Cairo with Islamist radicals from Hamas, aimed at limiting the violence.
Earlier yesterday, two Palestinian would-be suicide bombers blew themselves up without injuring anyone after border guards spotted them in the same area.
Israeli helicopters also blasted a Gaza City workshop overnight, causing no injuries, but the army insisted the operation was not in retaliation for the kibbutz shooting.
There attacks yesterday will further complicate US envoy Mr Mr David Satterfield's mission to the region, in which a plan calling for a de facto Palestinian state to be created next year with formal borders established by 2005, was discussed with Arab governments by US envoy Mr William Burns last month.
Both Israel and the Palestinian have approved it in principle but demand more time to for internal consultation.