Israeli troops battled militants across Gaza on Wednesday, including in the southern city of Rafah that had been a refuge for civilians, in an upsurge of the more than seven-month war that has killed tens of thousands of Palestinians.

Antagonism between Israel and the United Nations worsened as the Israeli army sought an explanation for footage showing armed men next to U.N. Palestinian relief agency vehicles. Separately, India was working to bring home the body of a U.N. staffer killed in Rafah by what the global body said was tank fire.

Prime Minister Benjamin Netanyahu’s army has in recent days pressed into the east of Rafah in pursuit of what it says are four Hamas battalions, despite warnings from its ally the U.S. and others to hold off to avoid mass civilian casualties.

Since Hamas’ Oct. 7 attack, Israel has killed more than 35,000 Palestinians, according to Gaza health officials, with 82 dead on Tuesday in the highest single-day toll for weeks.

Hamas-led gunmen killed some 1,200 people in their initial cross-border raid, according to Israeli tallies, and still hold 128 hostages.

In the northern Jabalia district, residents said Israeli tanks had destroyed clusters of homes but were facing heavy resistance from Hamas and its ally Islamic Jihad. “They are bombing houses on top of their inhabitants,” said Abu Jehad.

Islamic Jihad said it killed some foot soldiers in Jabalia, while Israel‘s military said it eliminated many gunmen in an area where it had declared major operations over months ago – but had also pledged to return to prevent armed factions regrouping.

DEATHS MOUNT

Israeli tanks have been massed around the eastern edges of Rafah and in recent days have been probing into built up areas of the city, where hundreds of thousands of displaced people have been sheltering from fighting elsewhere.

Residents said Israeli forces had pushed into three neighbourhoods and Palestinian gunmen were trying to prevent soldiers and tanks moving towards the centre.

Israel said its troops targeted a training compound, killing militants in close-quarters combat and finding many weapons.

Israel reported one death in south Gaza which public broadcaster Kan said was the first such fatality since the start of the Rafah ground operation last week. Netanyahu told CNBC broadcaster the operation could last weeks.

In the north, Israel said it had concluded an operation in the Zeitoun area, killing “dozens of terrorists”. Residents said tanks had pulled back from the area, with dozens of homes destroyed or damaged, while Palestinian medics said dozens of civilians had been killed and wounded.

Israel said its troops had identified fighters in the central logistics compound of the U.N. Palestinian relief agency UNRWA east of Rafah, demanding an explanation. Reuters verified the location of video released by the Israeli army but could not verify when it was filmed or the identity of the men.

“The U.N. has in part become a terrorist entity in itself because it cooperates with Hamas and covers for it,” Israel‘s ambassador to the U.N. Gilad Erdan told Army Radio.

UNRWA has denied cooperating with Hamas.

The agency said it was examining the images and would share information when possible. Senior Hamas official Sami Abu Zuhri told Reuters the men were there to protect aid distribution.

“These are false allegations and lies. This is a police force tasked with securing aid centres against acts of theft and looting,” Abu Zuhri told Reuters.

PROBE INTO U.N. FATALITY

The U.N. is investigating a strike on a car in Rafah this week that killed its first international staff member since Oct. 7, a retired Indian army officer en route to the European Hospital. It blamed tank fire in an area where only Israeli tanks were present.

The Israeli military said an initial inquiry had concluded the vehicle, whose route it was unaware of, had been hit in an active combat zone and the incident was under review.

Some 254 aid workers have been killed in Gaza since the war began, including 191 U.N. staff, according to the U.N..

Global watchdog The Committee to Protect Journalists said at least 105 media workers have also died.

As the fighting intensifies, ceasefire talks mediated by Qatar and Egypt are at a stalemate, with Hamas demanding a permanent end to attacks and Netanyahu’s government saying it will not stop until the group is annihilated.

Netanyahu opposes the creation of an independent Palestinian state, which most foreign powers see as the only long-term solution to a conflict stretching back seven decades.

U.S. Secretary of State Antony Blinken urged Israel to produce a clear plan for Gaza’s future, saying neither Israeli occupation nor Hamas governance were acceptable. “We also can’t have anarchy and a vacuum that’s likely to be filled by chaos.”

There was further unrest too in the second and larger occupied Palestinian territory, the West Bank.

Ayser Mohammad Safi, a 20-year-old Palestinian university student, was shot dead by Israeli forces in clashes in the city of Al-Bireh, according to official Palestinian news agency Wafa. Nearly 500 Palestinians have been killed by Israeli fire in the West Bank since Oct. 7, Palestinian authorities say.

In a reminder of the conflict’s regional ramifications, Yemen’s Iran-backed Houthis said they had attacked a U.S. warship and a vessel called “Destiny” in the Red Sea as part of a campaign of solidarity with the Palestinians.