JERUSALEM, (AFP) – Israel said it had largely secured the Gaza border and was evacuating nearby towns where the bodies of 1,500 Hamas militants had been recovered by Tuesday after days of gruelling battles outside the Palestinian enclave.

Prime Minister Benjamin Netanyahu has warned Israel’s military campaign following Saturday’s surprise onslaught was only the start of a sustained war to destroy Hamas and “change the Middle East”.

Fears of a regional conflagration have surged amid expectations of a looming Israeli ground incursion into Gaza, the crowded enclave from where Hamas launched its land, air and sea attack on the Jewish Sabbath.

The death toll in Israel has surged above 900 from the worst attack in the country’s 75-year history, while Gaza officials have reported 687 people killed so far.

Hamas gunmen killed more than 100 people in the kibbutz of Beeri alone, said Moti Bukjin, a volunteer with the charity Zaka that recovers bodies in accordance with Jewish law.

“They shot everyone,” he told AFP. “They murdered in cold blood children, babies, old people — everyone.”

Netanyahu compared the large-scale slaughter of Israeli civilians to the atrocities committed by the Islamic State group, also known as ISIS, when they controlled vast swathes of Syria and Iraq.

“Hamas terrorists bound, burned and executed children,” a seething Netanyahu said in a televised address to the grieving nation late Monday. “They are savages. Hamas is ISIS.”

The veteran leader at the helm of Israel’s hard-right coalition also called for an “emergency government of national unity” after years of political crisis and bitter societal divisions.

The Israeli army has called up 300,000 reservists for its “Swords of Iron” campaign and massed tanks and other heavy armour both near Gaza, and on the northern border with Lebanon.

The military said its forces had largely reclaimed the embattled south and the border around Gaza and dislodged holdout Hamas fighters from more than a dozen towns and kibbutzim.

“Around 1,500 bodies of Hamas (fighters) have been found in Israel around the Gaza Strip,” said army spokesman Richard Hecht, adding that security forces had “more or less restored control over the border” with the enclave.

– Threat to kill hostages –

Key ally the United States — which reported 11 of its own citizens killed, and more missing in the spiralling conflict — stressed its full support for Israel, as did Britain, France, Germany and Italy.

Their five leaders said they “recognise the legitimate aspirations of the Palestinian people” but said Hamas “offers nothing for the Palestinian people other than more terror and bloodshed”, in a joint statement released by the White House.

The five Western powers and many other nations have reported citizens killed, abducted or missing, also including Brazil, Cambodia, Canada, Ireland, Mexico, Nepal, Panama, Paraguay, Russia, Sri Lanka, Thailand and Ukraine.

Hamas has held around 150 hostages since its ground incursion, among them children, elderly and young people who were captured at a music festival where some 270 died.

On Monday, Hamas warned it would start killing hostages every time Israel launches a strike on a civilian target in Gaza without warning.

Fear and chaos reigned among the 2.3 million Palestinians living in the crowded and impoverished coastal territory that has been hammered by thousands of Israeli bombs.

Fireballs repeatedly lit up Gaza City before dawn on Tuesday as explosions shook the ground and sirens wailed.