GAZA (Reuters) - Recovery teams ventured into battlegrounds of the Gaza Strip on Thursday to gather bodies from the rubble, and Hamas officials said the Palestinian toll in Israel’s 13 day-old offensive rose to 765 dead.

Local ambulance crews and the Red Crescent, using a time slot coordinated with Israeli forces, said they collected rotting corpses in places that had been too risky to reach since Israeli forces began a ground attack six days ago.

They found four children starving beside the bodies of their mothers, dead many days, and evacuated scores of trapped and injured, the International Committee of the Red Cross said.

Israel lost 3 soldiers in fighting with Islamist militants who hold the Gaza Strip. Apart from a “friendly fire” incident which killed four, this was its heaviest one-day combat toll.

Ten soldiers have so far died in the campaign launched by Israel to crush Hamas forces and halt the firing of missiles from Gaza into Israel. Israel says it is doing what it can to avoid civilian casualties but accuses Hamas of deliberately placing its forces close to homes and Mosques.

At the United Nations, Western powers and Arab states reached an agreement in principle on a draft Security Council resolution that would call for an immediate ceasefire.

“In principle there is an agreement,” Arab League envoy ambassador Yahya Mahmassani told reporters.

It was not clear if they would vote on the resolution later in the day or on Friday.

Rescue work in Gaza was becoming increasingly dangerous.

The U.N. Relief and Works Agency (UNRWA), which feeds half of Gaza’s 1.5 million people, stopped work after a driver was killed by an Israeli tank. It had earlier said two drivers died.

Operations would be suspended until the Israeli army could guarantee security.

The Hamas ministry of health said 34 percent of the dead and 35 percent of over 3,000 injured were children. There was no independent confirmation of the figure.

“The danger to medical staff and the difficulty of extracting the injured from collapsed buildings makes proper evacuation and estimation of casualties difficult,” the U.N. Humanitarian Coordinator’s daily field report said.

“Civilians, notably children who form 56 percent of Gaza’s population, are bearing the brunt of the violence. As one of the most densely populated places in the world, it is clear that many more civilians will be killed if the conflict continues.”

BROTHERS IN DEATH

Around 20 rockets hit Israel on Thursday, fewer than at the start of the war but not the total halt it wants so that “quiet will reign supreme,” as Prime Minister Ehud Olmert said.

Rockets have killed three Israeli civilians since the offensive began. Olmert said Israel’s goal had not been achieved and a decision on further military action lay ahead.

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Aside from a 3-hour ceasefire which Israel ordered for the second day, to let Gaza civilians venture out, there was no let-up in fighting. Air strikes and ground attacks killed at least nine civilians and three gunmen, medical officials said.

The dead included two brothers aged six and 13, killed when an Israeli air strike missed a group of Islamic Jihad fighters.

A Ukrainian woman, who could have left, was killed in her home by a tank shell, along with her son. The father said his wife was sliced in two, his 18-month-old son only recognizable “by his teeth.”

In Washington, the U.S. Senate adopted a bipartisan motion

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“reaffirming Israel’s inalienable right to defend against attacks from Gaza,” said majority leader Harry Reid.

The United States would do the same if “rockets and mortars coming from Toronto in Canada” hit Buffalo, New York, he said.

LEBANON FRIGHT

Israel says it accepts the “principles” of a ceasefire proposal by Egypt and the European Union, and Washington has urged the Jewish state to study details of the plan.

Hamas, shunned by the West for espousing violence, said it was still considering the ideas. But the militants say they will never accept Israel, whose establishment in war 60 years ago dispossessed and uprooted Palestinian people.

European governments offered to back the plan with an EU border force to stop Hamas rearming via tunnels from Egypt. The deal would also address Palestinian calls for an end to Israel’s economic blockade of the Gaza Strip.

Relations between Israel and the Vatican, never easy, chilled further over Gaza. The Jewish state condemned an aide to Pope Benedict for calling Gaza “a big concentration camp,” the Vatican’s toughest criticism of Israel since its offensive.

Foreign Ministry spokesman Yigal Palmor said Israel was astounded at “the vocabulary of Hamas propaganda, coming from a member of the College of Cardinals.”

The ICRC accused Israel of violating the rules of war by delaying ambulance access to the house where its team found children huddled beside corpses, 80 meters (yards) from the Israeli army.

The Red Cross said the army must have known of the situation but did not help the wounded, in violation of international law.

Israeli nerves were rattled in the morning when a rocket from southern Lebanon hit an old people’s home in Nahariya, raising fears that Hezbollah fighters were opening a second front to relieve pressure on Gaza.

Israel fought a 34-day war with Shi’ite Hezbollah guerrillas in 2006 and is no hurry to engage them now. It responded with a few artillery rounds and played down the rocket attack.