Israeli bombs have killed the wife and infant son of elusive Hamas military commander Mohammed Deif just hours after a truce broke down in a hail of rockets and gunfire.
Five people died in the strike on a Gaza house, including Mr Deif’s family, according to Hamas officials.
It was not immediately clear whether Mr Deif was there at the time of the strike. He has escaped numerous Israeli assassination attempts in the past.
Palestinian militants launched dozens of rockets and Israel responded with airstrikes after Egyptian efforts to mediate a lasting truce in the month-long Gaza war failed.
Since the truce collapsed, at least 20 Palestinians have been killed and more than 120 wounded, Gaza health ministry official Ashraf al-Kidra said.
The Israeli Defence Force said it carried out nearly 100 airstrikes on Gaza targets, and Palestinians had fired more than 140 rockets at Israel since the temporary truce collapsed.
About 2,000 reserve soldiers who had been sent home two weeks ago when fighting seemed to have simmered down were called up for duty again yesterday, the military said.
The breakdown in talks and the resumption of violence marked a bitter ending to nearly a week of Egyptian-led diplomacy meant to end the war, which has reduced Gaza neighbourhoods to rubble and claimed more than 2,000 lives, mainly Palestinians.
In Cairo, Moussa Abu Marzouk, a senior Hamas leader, said three others in the same building as Mr Deif’s family were also killed.
Israel has not formally commented on the strike but local media quoted an anonymous official as saying it was meant for Mr Deif.
And Yaakov Peri, an MP from the centrist Yesh Atid party and former director of Israel’s Shin Bet internal security service, said: “If there was intelligence information that Mohammed Deif was not at home, then the house would not have been blown up.”
At least 21 people were wounded in a separate airstrike that hit a building that houses offices of Hamas’ Al-Aqsa TV station, a Gaza health ministry spokesman.
Air raid sirens wailed in southern Israeli cities yesterday morning warning of incoming rockets from Gaza.
There were no reports of injuries, though a piece of a rocket that was intercepted near Tel Aviv on Tuesday night fell on a busy road.
Meanwhile, Israel’s civil defence authority ordered the reopening of public bomb shelters within 50 miles of Gaza.
Hamas is seeking an end to an Israeli-Egyptian blockade imposed when it seized power in Gaza in 2007, while Israel wants guarantees that the Islamic militant group will disarm.
In nearly a week of indirect talks, Egypt appears to have made little headway. Late on Monday, it secured a 24-hour ceasefire extension to allow for a last-ditch attempt to reach a deal.
Yesterday, the Egyptian foreign ministry expressed “deep regret” over the breaking of the ceasefire.
It said it “continues bilateral contacts” with both sides aimed at securing a lasting truce that “serves the interest of the Palestinian people, especially in relation to the opening of the crossings and reconstruction”.
An Egyptian compromise proposal calls for easing the blockade, but not lifting it altogether, nor opening the territory’s air and seaports, as Hamas has demanded.
While the plan does not require Hamas to give up its weapons, it would give the largely secular, Western-backed Palestinian president Mahmoud Abbas – whose forces were ousted by Islamist Hamas in 2007 – a foothold back in Gaza, running border crossings and overseeing internationally-backed reconstruction.
The disagreements have focused around the lifting of the blockade, with Hamas pushing for far more dramatic concessions than Israel is willing to offer. The blockade has greatly limited the movement of Palestinians in and out of the territory of 1.8 million people, restricted the flow of goods into Gaza and blocked virtually all exports.
Israel has said the blockade is needed to prevent Hamas and other militant groups from getting weapons.