GAZA/OCCUPIED JERUSALEM: Israel launched more than 30 aerial attacks in Gaza Saturday, killing five Palestinians, and militants fired rockets at Israel as the conflict entered a second month, defying international efforts to negotiate an agreement for an extended cease-fire.

The violence seemed to delay any progress in talks brokered by Egypt aimed at securing another truce. Israel had no plans to send negotiators back to Cairo "as long as the shooting goes on," an Israeli official said on condition of anonymity.

Medical officials in Gaza said two Palestinians were killed when their motorcycle was bombed and the bodies of three others were found beneath the rubble of one of three bombed mosques.

Another attack reduced a security complex belonging to Gaza's dominant Hamas faction to a huge cloud of smoke, but there were no casualties. In other attacks, three houses were bombed, and fighter planes strafed open areas, medical officials said.

The Israeli military said that since midnight it had attacked more than 30 sites in the coastal enclave, without specifying the targets.

Gaza militants fired 15 rockets at towns in Israel's south Saturday setting off alarm sirens but causing no damage or injuries, a military spokeswoman said.

Since the end of a 72-hour truce Friday, Gaza militants have fired more than 65 rockets at Israel, military officials said. Two Israelis were hurt by a mortar attack Friday.

Israeli air strikes killed five Palestinians Friday, among them a 10-year-old boy near a mosque in Gaza City.

Egypt, backed by American and European mediators, has made no visible progress toward resuming the cease-fire that had halted fighting for three days between Israel and Gaza militants that began on July 8.

Egypt was expected to pursue its diplomacy Saturday, meeting Palestinian officials in Cairo, but it wasn't clear how much progress could be made if Israeli representatives didn't show up.

Both sides remain apart on terms for renewing the cease-fire, with each blaming the other for refusing to extend it.

A diplomatic source familiar with the talks told Reuters it could take at least two days to see if it was possible to work out another truce. A sticking point was Israel's demand for guarantees that any reconstruction supplies sent to Gaza would not be used by Hamas to construct more tunnels of the sort that Palestinian fighters have used to infiltrate Israel.

Egypt is mediating the talks but meeting separately with each party. Israel and Hamas deny each other's legitimacy, with Hamas rejecting Israel's right to exist and Israel rejecting Hamas as a terrorist organisation.

Citing security concerns over continued rocket fire, Israeli police banned an anti-war protest planned for Tel Aviv Saturday, saying regulations prohibited large gatherings in areas at risk of attack.

By resuming attacks against Israel, Gaza militants appeared to be trying to ramp up pressure and making it clear they were ready to fight on to fulfil a goal of ending a blockade of the territory that both Israel and Egypt have imposed.

Heavy civilian casualties and destruction during Israel's campaign against militants in packed residential areas of the Gaza Strip have raised international alarm over the past month.

Gaza officials say the war has killed 1,886 Palestinians, most of them civilians. Israel says 64 of its soldiers and three civilians have died in the fighting that followed a surge in Palestinian rocket salvoes into Israel.

Israel expanded its air and naval bombardment of the Gaza Strip into a ground offensive on July 17, and pulled its infantry and armour out of the enclave on Tuesday after saying it had destroyed more than 30 infiltration tunnels dug by militants.

The White House urged Israel and the Palestinians to do what they could to preserve civilians after having failed to extend their ceasefire. Spokesman John Earnest said Friday "the United States is very concerned" about the renewed violence.

U.N. Secretary-General Ban Ki-moon urged the parties "not to resort to further military action that can only exacerbate the already appalling humanitarian situation in Gaza."

At a rally in South Africa, Nobel laureate Desmond Tutu accused Israel of behaving like a "barbaric bully" in Gaza.

Israel said ahead of the truce's expiration Friday it was ready to agree to an extension. Hamas did not agree.

Hamas spokesman Sami Abu Zuhri said Israel had rejected most of the group's demands. The Palestinians want Israel to agree in principle to lift a Gaza blockade, release prisoners and permit the opening of a sea port.

"There is no going back and the resistance will continue ... there is no retreat from any of our demands," Abu Zuhri said.

Israel has resisted easing access to Gaza, suspecting Hamas could restock with weapons from abroad.

Israeli Justice Minister Tzipi Livni, a member of Prime Minister Benjamin Netanyahu's security cabinet, said the issue of a sea port should be part of wider peace negotiations with the Palestinians and that Hamas should not at this time be rewarded for "using force against Israeli citizens."

In related violence, a Palestinian man died a day after being shot by Israeli troops quelling a protest in Hebron. Israeli gunfire killed another Palestinian protester in the West Bank, medical officials said.