Palestinian Khaled Sharmi, 67, inspects the damage in the Al Aqsa Martyrs mosque destroyed by an overnight Israeli strike, in Gaza City.

Palestinian Khaled Sharmi, 67, inspects the damage in the Al Aqsa Martyrs mosque destroyed by an overnight Israeli strike, in Gaza City.

Israeli air strikes pummelled a wide range of targets in the Gaza Strip today as the UN chief and the US Secretary of State began an intensive effort to end more than two weeks of fighting that has killed at least 570 Palestinians and 29 Israelis.

Overnight, Israel bombed five mosques, a sports complex and the home of the late Hamas military chief, a Gaza police official said.

The Israel military announced early today that two more soldiers had died – one from sniper fire yesterday and one from as yet unexplained causes – bringing the military death toll to 27. It is the highest number of Israeli military fatalities for any campaign since the 2006 Lebanon war. Two Israeli civilians have also been killed in the latest conflict.

The Israeli campaign, launched on July 8, is aimed at stopping Hamas rocket fire into Israel – some 2,000 rockets have been launched over the past two weeks, the military says – and destroying tunnels which the military claims Hamas has constructed from Gaza into Israel for attacks against Israelis.

The air strikes set off huge explosions that turned the night sky over Gaza City orange early today. The sound of the blasts mixed with the thud of shelling, often just seconds apart, and the pre-dawn call to prayer from mosque loudspeakers.

United Nations Secretary-General Ban Ki-moon

United Nations Secretary-General Ban Ki-moon

The strikes came as UN secretary-general Ban Ki-moon and US Secretary of State John Kerry met in Cairo late yesterday to launch the highest-level push yet to end the deadly conflict. The UN has said the majority of the Palestinians killed were civilians, among them dozens of children.

In the Gaza Strip, Israeli aircraft hit more than 70 targets, including the home of the late leader of Hamas’s military wing, five mosques and a sports complex, said Gaza police spokesman Ayman Batniji. There were no casualties in the mosques or at the sports complex, which includes a gym, three martial arts studios and a soccer field.

Tank shells also damaged several houses along the eastern border of the territory, he said. At least 19 fishing boats were burned by Israeli navy shells fired from the Mediterranean Sea, he added.

Six upper floors of a Gaza high-rise collapsed on to the two lower storeys, buckling them into rubble. At the scene, construction company owner Ehab Batch, 40, and several of his workers were trying to retrieve documents from what had once been the company’s second floor offices.

Mr Batch, who said he had had no work in the past year because Egypt had blocked border tunnels that bring in construction material, said Gaza needs an immediate ceasefire and a deal which would open all border crossing points.

“We need Gaza people to have a (normal) life, as all the people in the world,” Mr Batch said.

Among the facilities hit overnight were three homes, including one where three women from the same family died, according to Gaza health official Ashraf al Kidra.

But prospects for a truce remained elusive.

Egypt, Israel and the US back an unconditional ceasefire, to be followed by talks on a possible new border arrangement for Gaza. Israel and Egypt have severely restricted movement in and out of Gaza since Hamas seized the territory in 2007.

Hamas, with some support from Qatar and Turkey, wants guarantees on lifting the blockade before halting fire. The Islamic militant group has no faith in mediation by Egypt’s rulers, who deposed a Hamas-friendly government in Cairo a year ago and tightened restrictions on Gaza – to the point of driving Hamas into its worst financial crisis since its founding in 1987.

Israeli soldiers on a 155mm M109 Dores self-propelled howitzer fire a shell towards Gaza.

Israeli soldiers on a 155mm M109 Dores self-propelled howitzer fire a shell towards Gaza.

The top Hamas leader in Gaza, Ismail Haniyeh, said yesterday that Gaza‘s 1.7 million people share Hamas’s goal of forcing Israel and Egypt to lift the blockade.

“We cannot go back, we cannot go back to the silent death” of the blockade, he said. “Gaza has decided to end the blockade by its blood and by its courage.”

After a meeting with Egyptian Foreign Minister Sameh Shukri, Mr Ban said “violence must stop by all sides”, and they must enter negotiations, apparently siding with Cairo’s approach.

“We can’t claim victory simply by returning matters to where they stood before they led to terrible bloodshed,” the UN chief said.

The border blockade has set Gaza back years, wiping out tens of thousands of jobs through bans on most exports and on imports of vital construction materials which Israel says could be diverted by Hamas for military use. Israel allows many consumer goods into Gaza, but experts say Gaza‘s economy cannot recover without a resumption of exports.

The Rafah passenger crossing with Egypt is Gaza‘s only gate to the world, but Egypt has tightened restrictions over the past year, allowing only medical patients, Muslim pilgrims and Gazans with foreign passports to travel.

Yesterday, US President Barack Obama reaffirmed his belief that Israel has the right to defend itself against rockets being launched by Hamas into Israel. Yet, he contended that Israel’s military action in Gaza had already done “significant damage” to the Hamas terrorist infrastructure and said he does not want to see more civilians getting killed.

On arrival in Cairo, Mr Kerry announced that the US will send 47 million dollars in humanitarian aid for tens of thousands of Palestinians who fled their homes in the coastal territory to escape the violence. His top aides warned, however, that achieving an immediate and lasting ceasefire would be difficult and he hoped to make any progress over the next several days to secure even a temporary pause in the bloodshed.

It was not clear exactly what Israel and Hamas would each demand in return for agreeing to a truce now, but senior State Department officials said the issue of opening border crossings – potentially into Israel and Egypt – was under discussion.

“We will work to see if there is some way to not only arrive at a ceasefire of some kind but to get to a discussion about the underlying issues,” Mr Kerry said at the start of his meeting with Mr Ban. “Nothing will be resolved by any ceasefire, temporary or long, without really getting to those issues at some point and that’s what we need to do.”

Mr Kerry remained in Cairo for more meetings with top Egyptian officials. But there were no immediate plans for face-to-face talks with officials from Qatar, Turkey, Israel and the West Bank.