An Israeli airstrike in Gaza killed three senior commanders of the Hamas military wing Thursday, delivering a likely blow to the organization's morale and highlighting the long reach of Israel's intelligence services.
The pre-dawn strike levelled a four-story house in a densely populated neighbourhood of the southern town of Rafah, killing six people, including the three senior Hamas commanders.
The trio had played a key role in expanding Hamas' military capabilities in recent years, including digging attack tunnels leading to Israel, training of fighters and smuggling of weapons to Gaza, Israel said.
It was not immediately clear if their assassination would prompt a change in Hamas strategy in the current round of fighting with Israel or diminish the group's ability to fire rockets at Israel. The military wing, the Izzedine al-Qassam Brigades, is a secretive organization.
Sami Abu Zuhri, a Hamas spokesman, said Israel "will not succeed in breaking the will of our people or weaken the resistance," and that Israel "will pay the price."
Israeli Prime Minister Benjamin Netanyahu praised the "superior intelligence" of the Shin Bet security service and the military's "precise execution" of the attack.
The killing of the three top Hamas commanders will likely buy Netanyahu some time as the Israeli public becomes increasingly impatient with the government's inability to halt rocket fire from Gaza.
Israel and Hamas identified the three commanders killed in the 3 a.m. airstrike in Rafah's Tel Sultan neighbourhood as Mohammed Abu Shamaleh, Raed Attar and Mohammed Barhoum.
Gaza police and witnesses said several missiles hit the four-story building.
Hamza Khalifa, an area resident said the house was struck without warning. "We only heard multiple F-16 (warplane) missiles, one after the other, six or seven missiles," he said.
Several hours later, a large earth mover was still clearing mounds of debris and wreckage.
In pinpointing the whereabouts of the Hamas commanders, Israel likely relied to some extent on local informers. Israel has maintained a network of informers despite its withdrawal from Gaza in 2005, in some cases using blackmail or the lure of exit permits to win co-operation.
Al Majd, a website linked to the Hamas security services, said Thursday that seven suspected informers were arrested in recent days and that three were killed "after the completion of the revolutionary procedures against them." The wording suggested they did not receive a trial.
It was the second time during the Gaza war that the website announced suspected informers had been killed by Hamas.
The Rafah attack came a day after an apparent Israeli attempt to kill the top Hamas military leader, Mohammed Deif, in an airstrike on a house in Gaza City.
Deif's wife and an infant son were killed in that strike, but the Hamas military wing said Deif was not in the targeted home at the time.
The back-to-back targeting of top Hamas military leaders came after indirect Israel-Hamas negotiations in Cairo on a sustainable truce broke down Tuesday. Gaza militants resumed rocket fire on Israel, even before the formal end of a six-day truce at midnight that day.