At least 85 Palestinians have been killed in Israeli air strikes in Gaza since midnight, the territory’s Hamas-run health ministry has said.

Hours later, Israel’s military said it had intercepted three rockets, which Hamas’s armed wing said it fired at Tel Aviv in response.

It comes after Israel resumed its bombing campaign and ground operations in Gaza this week, with air strikes having already killed more than 500 people over the past two days, according to the health ministry.

The Israel Defense Forces (IDF) said on Thursday that it had started a ground operation in northern Gaza. There had been a reprieve from large-scale military action since January, when a ceasefire had begun.

Gaza’s health ministry also reported that 133 people were injured in the latest attacks on Thursday.

Israel resumed attacks on Tuesday as talks to extend the ceasefire deal failed to progress, warning that they would intensify until Hamas released the remaining hostages.

Israel says Hamas is still holding 59 hostages, 24 of whom are believed to still be alive.

IDF spokesperson Col Avichay Adraee said Hamas had fired three rockets from southern Gaza. One was intercepted, while the other two fell in an “open area”, he wrote in a post on X.

The Israeli military said earlier on Thursday that it had begun “targeted ground activities” to create what it called a “partial buffer between the north and south” of Gaza. It called the action a “limited ground operation”.

Col Adraee said forces were deployed up to the centre of a strip, known as the Netzarim Corridor, which divides northern and southern Gaza.

Gaza’s health ministry says at least 591 people, including more than 200 children, have been killed since Israel resumed fighting on Tuesday.

Israeli government spokesman, David Mencer, blamed Hamas for the resumption of violence, saying it had “forced this escalation, it rejected every hostage deal, including the offers mediated by the US and others”.

Meanwhile, five staff members of the UN’s Palestinian refugee agency Unrwa were among those killed over the “past few days”, the agency’s chief Philippe Lazzarini said in a post on X.

“They were teachers, doctors and nurses,” he added, warning that “the worst is yet to come” amid the ongoing ground invasion.

On Wednesday, the UN said that one of its workers had been killed after its compound in Deir al-Balah in central Gaza was damaged. While it said the circumstances remain unclear, UN Office for Project Services head Jorge Moreira said it was “not an accident” and “at least an incident”.

Gaza’s health ministry blamed an Israeli strike, which it said injured five others. Israel’s military said it did not attack the compound but was investigating the incident.

The US – a major weapons supplier to Israel – said that it was committed to international law regarding the supply of weapons supplies.

White House press secretary Karoline Leavitt said US President Donald Trump “fully supports Israel and the IDF in the actions that they’ve taken in recent days”.

UK Foreign Secretary David Lammy confirmed on Thursday that a UK national had been wounded in the compound attack. It comes after a charity said one of its workers, a 51-year-old British bomb disposal expert, had been injured.

“Our priority is supporting them and their family at this time,” he told MPs.

At the Nasser Hospital in Khan Younis, southern Gaza, Qasim Abu Sharqiya said his two-year-old son, Omar, had been born through in vitro fertilisation (IVF) after five years of trying.

“They bombed a tent next to us and he died,” he told AFP. “Omar is my only son, oh world, and I have no one else.”

A doctor there, Tanya Haj Hassan, told the BBC’s Newshour that she had heard of at least 76 people who “didn’t even make it into the ER” but were taken “straight to the mortuary”.

She recalled “a level of horror and evil that is really hard to articulate – it felt like Armageddon”.

Thousands of Israelis joined anti-Netanyahu protests in Jerusalem and Tel Aviv, calling for the return of the hostages.

Several arrests were made, with police in Jerusalem deploying a water cannon against demonstrators.

Elsewhere, Yemen’s Houthi rebels fired a ballistic missile at Israel on Thursday, aiming for Ben Gurion Airport near Tel Aviv, the Iran-backed group’s military spokesperson said.

No injuries were reported and the IDF said the missile was stopped before entering Israel.

Israel’s Prime Minister Benjamin Netanyahu said on Tuesday that it had “resumed combat in full force” and any ceasefire negotiations would now take place “under fire”.

A group representing hostages’ families has accused the Israeli government of choosing “to give up the hostages” by launching new strikes.

Israel and Hamas have failed to agree how to take the ceasefire beyond the first phase, which expired on 1 March.

Hamas did not agree to a renegotiation of the ceasefire on Israel’s terms, although it offered to release a living American hostage and four hostages’ bodies as mediators tried to prolong the ceasefire.

Israel blocked all food, fuel and medical supplies entering Gaza at the beginning of March in order to put pressure on Hamas. It accused Hamas of commandeering the provisions as part of its strategy against Israel, though did not provide evidence for this claim.

The war was triggered by Hamas’s attack on Israel on 7 October 2023, in which about 1,200 people, mainly civilians, were killed and 251 other taken hostage. Twenty-five Israeli and five Thai hostages were released alive during the first phase of the ceasefire.

Israel responded to the 7 October attack with a massive military offensive, which had killed more than 48,500 Palestinians, mainly civilians, before Israel resumed its campaign, the Hamas-run health ministry says. Israel’s offensive has also caused huge amounts of destruction to homes and infrastructure.