Three Israelis are now known to have died in a suicide bomb attack outside a shopping centre in the coastal city of Netanya.
It is a heavy blow to those who had been hoping that a fragile five-month truce would hold.
Violence had fallen sharply after the Palestinian and Israeli leaders agreed to a ceasefire in February.
A spokesman for the Israeli Prime Minister had this reaction: “The Palestinian Authority and the government of Abu Mazen are doing nothing to stop terrorist activity. We’re willing to deal honestly with the Palestinians. Instead of that we’re getting the Palestinian terrorist groups messing with us.”
Palestinian President Mahmoud Abbas denounced the terrorist attack.
“It’s a crime against the Palestinian people,” he said. “Those traitors are working against Palestinian interests. There is no rational man who would do those things on the eve of the Israeli withdrawal from 22 settlements.”
A group known as the Islamic Jihad has claimed responsibility for the attack. It says it remains committed to the truce, but reserves the right to retaliate against certain Israeli actions.