The Israeli military said it rescued four hostages held since October in a raid in the central Gaza Strip on Saturday while Palestinian officials said an Israeli attack in the same area killed more than 50 people.

It was not immediately clear if the hostage rescue and the deadly Israeli assault were part of the same operation but both took place in al-Nuseirat, an often embattled area in the eight-month-old war between Israel and Gaza's ruling Hamas.

The Israeli military named the rescued hostages as Noa Argamani, 25, Almog Meir Jan, 21, Andrey Kozlov, 27, and Shlomi Ziv, 40. They were taken to hospital for medical checks and were in good health, the military said.

They were all kidnapped from the Nova music festival during Palestinian militant group Hamas’ deadly raid on Israeli towns and villages near Gaza on October 7, an attack which precipitated the devastating war in the besieged Hamas-run enclave.

Hamas's raid killed some 1,200 people, according to Israeli authorities, and Israel's subsequent bombardment and invasion of Gaza has killed at least 36,801 Palestinians, according to an updated tally by the enclave's health ministry on Saturday.

Palestinian militants took around 250 hostages back to Gaza on October 7. There are 116 now left in Gaza, according to Israeli tallies, including at least 40 whom Israeli authorities have declared dead.

Israeli News 12 broadcast footage of Argamani reunited with her father, smiling and embracing him. Video of Argamani’s kidnapping had circulated soon after she was dragged into Gaza by gunmen on October 7.

The Israeli military had said earlier on Saturday it was targeting militant infrastructure in al-Nuseirat, an unusual announcement because it does not normally report on its operations while they are still underway.

Al-Nuseirat, a historic Palestinian refugee camp, has been subjected to heavy Israeli bombing during the war and there also has been fierce ground fighting in its eastern areas.

Gaza’s health ministry meanwhile reported on Saturday that Israeli military assaults in al-Nuseirat had killed and wounded dozens of people including women and children. The ministry did not say how many of the fatalities were combatants.

A health ministry official put the death toll at more than 50, saying emergency response teams were trying to ferry the dead and wounded to hospital in the nearby city of Deir al-Balah but many bodies were still lying in the streets, including around a market district.

Local residents said al-Nuseirat had come under heavy Israeli drone and air strikes, and that those who were killed included women and children.

Israeli military spokesman Rear Admiral Daniel Hagari said the rescue operation was carried out under fire in the heart of a residential neighbourhood where he said Hamas had been hiding captives among Gaza civilians under armed guard of militants.

In a televised news conference, Hagari said one Israeli soldier had been badly wounded. The Israeli forces returned fire, Hagari he said, including with airstrikes.

The Gaza war shows no signs of slowing even as Israel's chief ally the United States presses for a ceasefire and a deal that would free the remaining hostages held by Hamas in exchange for releases of Palestinians imprisoned in Israel.

The war has destabilised the wider Middle East, drawing in Hamas’s main backer Iran and its heavily armed Lebanese ally Hezbollah, which Israeli officials are threatening to go to war with on Israel's northern border.