At least 17 people, nearly all women and children, have been killed in Israeli bombing of a school turned shelter in the Nuseirat refugee camp in the central Gaza Strip, medics in the territory have said.

The strike, the latest bombing of a school sheltering displaced people across Gaza, came as the Qatari television network Al Jazeera accused Israel of turning its journalists reporting from north Gaza into targets after the Israeli military claimed a day earlier that six reporters were members of Hamas or Palestinian Islamic Jihad.

There were also reports of renewed international efforts at brokering a ceasefire in the year-long Israel-Hamas war after a two-day visit to the region by the US secretary of state, Antony Blinken.

Rescue efforts were still under way at the school in Nuseirat camp, said Mahmoud Bassal, a spokesperson for Gaza’s civil defence agency. The Israeli military said the school was being used as a Hamas command and control centre.

Another 42 people were wounded in the strike in the overcrowded camp, according to nearby al-Awda hospital, which received the casualties. Among the dead were 13 children under the age of 18 and three women, it said.

Israel continues a new offensive in northern Gaza, which Bassal said had killed 770 people since it began on 6 October. Thousands of people have fled to the relative safety of the south of the strip in recent days.

The civil defence agency said on Thursday it had been forced to suspend operations in northern Gaza after what it called threats from the Israeli military to “bomb and kill” rescue crews working in Jabaliya camp, the focus of the new Israeli offensive. Three workers had been wounded and another five arrested by the Israeli army, and the crews’ only working fire engine was destroyed by tank fire, he said.

A medic was killed by Israeli fire and another detained on his way to work, according to the Indonesia hospital, one of three struggling medical facilities still operating in the area, on Thursday.

Israel says the operation is necessary to prevent Hamas from regrouping and denies allegations that it intends to expel the remaining 400,000 people still living in the northern third of Gaza. Israel has split the territory in two by building the Netzarim corridor, which bisects the strip just south of Gaza City.

On Wednesday the Israeli military published documents which it said it had found in Gaza that proved that six Al Jazeera journalists had a military affiliation to Hamas or Palestinian Islamic Jihad. The papers could not be immediately independently verified.

In a statement on Thursday, Al Jazeera said the Israel accusations were “criminal, draconian and irresponsible” and “part of a wider pattern of hostility”. Several of the network’s journalists have been killed by Israeli fire in the Gaza war, deaths the Israeli military denies were deliberate.

Israel outlawed Al Jazeera earlier this year for what it termed “security reasons”, and raided its offices in the occupied West Bank.

The Committee to Protect Journalists’ Middle East programme said on X that the allegations amounted to the smearing of Palestinian journalists “with unsubstantiated terrorist labels”.

Indirect talks aimed at a ceasefire and hostage release deal in the war in Gaza, mediated by the US, Qatar and Egypt, have been deadlocked since the assassination in July ofIsmail Haniyeh, the leader of Hamas and its main negotiator. The attack in the Iranian capital of Tehran is believed to have been carried out by Israel, although the country has not claimed responsibility.

The international community has pushed for a return to negotiations after Israel’s killing this month of the architect of the 7 October attacks, Yahya Sinwar, who had the final word on Hamas’s position in talks and had repeatedly blocked progress towards a deal.

Blinken, the US secretary of state, said after meetings in Doha with the Qatari leadership on Thursday that Israeli and US negotiators were expected to reconvene in “the coming days”. The Israeli prime minister’s office confirmed later on Thursday that one of the country’s main negotiators, the Mossad chief, Ronen Bar, would travel to Doha on Sunday.

Hamas, which has yet to name Sinwar’s successor, said on Thursday that delegations from the group were visiting Turkey, Qatar and Russia and were in contact with officials from the UN, Egypt and Iran.

Blinken has made more than a dozen trips to the Middle East over the past year in an effort to end the war in Gaza and calm regional tensions with Iran and its allies, but has come away empty-handed almost every time. He also announced an additional $135m (£104m) in aid to the Palestinians, while urging Israel not to block aid from entering Gaza.

Separately on Thursday, France hosted an international aid conference for Lebanon, but diplomatic efforts to end the new ground war between Israel and the powerful Lebanese group Hezbollah are yet to bear fruit.