Three of Hamas’s most senior military commanders have been killed in pre-dawn air strikes on Rafa in the south of the Gaza Strip.



Hamas announced the deaths of Mohammed Abu Shamalah, Raed Attar and Mohammed Barhoum on Thursday morning. The loss of the military commanders is a serious blow to the organisation.



There was still no definitive word on the fate of Mohammed Deif, Hamas’s top military figure, whose wife and eight-month-old son were killed on Tuesday evening when five one-tonne bombs struck a house in Gaza City.



Israeli military analyists said intelligence indicated Deif was at the house and that it was virtually impossible that anyone could have survived the destructive force of the bombing. A third unidentified person also died in the air strike.



The Israel Defence Forces said it struck 20 targets over Wednesday night and into Thursday morning.



It confirmed it had “eliminated senior Hamas terrorists Raed Attar and Mohamed Abu Shamala” but made no mention of Barhoum.



“Raed Attar played a major role in tunnel infiltrations, terror attacks that killed Israelis, and the kidnapping of [Israeli soldier] Gilad Shalit. Abu Shamala, commander of Hamas forces in [southern] Gaza, was directly involved in dozens of terror attacks, including the murders of IDF soldiers.” the IDF statement said.

As the death toll in Gaza rose well above 2,000 on Wednesday, the Israeli prime minister, Binyamin Netanyahu, compared the Hamas movement in Gaza to the Islamic State (Isis), calling the two groups a “branch of the same tree”.

At a press conference on Wednesday night Netanyahu said the Gaza war launched on 8 July “will be a continued campaign” aimed at restoring “calm and safety” to Israeli citizens.

He said the latest bout of Israeli military action in Gaza was “the harshest blow Hamas has taken since its foundation” and warned that if Hamas rocket fire continued Israel would hit back “sevenfold”. “This is a continuous campaign. The struggle against terror lasts for years,” he said.

The defence minister, Moshe Ya’alon, added that Israel “had killed hundreds of Hamas terrorists” and would continue to do so.

The UN security council expressed “grave concern” at the resumption of hostilities and called upon the parties to resume negotiations to urgently reach a “sustainable and lasting ceasefire”.

The 15-member council also “called upon the parties to prevent the situation from escalating and to reach an immediate humanitarian ceasefire”.

Speaking at a press conference in Gaza City, al-Qassam Brigades spokesman Abu Obeida warned of rocket attacks on Ben Gurion airport on Thursday, calling for airlines to suspend flights from 6am.

He told Israelis to avoid public gatherings and warned citizens in the country’s south not to leave bomb shelters.

On Wednesday hundreds of Palestinians attended the funerals of Deif’s wife, Vidad Asfura, 27, and son, Ali, in Jabaliya camp in northern Gaza.

Hamas had urged Gazans to turn out in force for the funeral but witnesses said the thousands-strong crowds, militant presence and gunfire that often mark funerals in Gaza were conspicuously absent.

Hundreds of civilians who had returned to their homes after eight days of relative quiet in Gaza fled back to UN shelters as Israel called up thousands of reserve troops and massed tanks and armoured personnel carriers on the border. Hawkish members of the Israeli cabinet on Wednesday repeated calls for an occupation of the Palestinian coastal enclave, which Israel evacuated under Ariel Sharon’s leadership in 2005.

Efforts to reach a diplomatic resolution to the conflict drew to a halt dramatically in Cairo as fire resumed on Tuesday evening. Negotiations showed no sign of restarting on Wednesday. Israel withdrew its delegation as soon as violence broke out and Hamas called for the Palestinian delegation to return home.

Israel has blamed Hamas for breaking the ceasefire and triggering a resumption of violence with the firing of three rockets, which landed in open land near the southern city of Beersheba on Tuesday night.

The Palestinians have blamed Israel for the failure of the truce and the return to violence. The Palestinian Liberation Organisation suggested in a statement that the rocket attack that provoked the Israeli withdrawal could have been manufactured by Israel as an excuse to abandon the talks.

“Israel … alleges that it was responding to three rockets launched from the Gaza districts – which supposedly landed in open areas and caused no deaths, injuries or damage,” the PLO said in a statement.

“This launch has not been confirmed and no Palestinian resistance group has claimed responsibility. Israel has used the alleged rocket fire as a pretext for continuing to target Palestinian civilians.”

The Palestinian president, Mahmoud Abbas, was due to meet the Hamas leader, Khaled Meshaal, in Doha, Qatar, late on Wednesday, as the Palestinian Authority continues to try to steer the peace process. Hamas signed a deal with Fatah in April this year to set up a unity government and the PA has taken the lead in talks between Israel and Hamas, who refuse to negotiate directly with each other.

With the Sisi government in Egypt hostile to the Islamist leadership in Gaza, Hamas is looking to Qatar for diplomatic support.

Michael Stephens, deputy director at the Royal United Services Institute for Defence and Security Studies in London, said: “Qatar is basically Hamas’s last ally. Given that Turkey is struggling and failing to insert itself into the process, Doha really is the only game in town.”