DEIR AL-BALAH, Gaza Strip (AP) — An Israeli strike on a school in central Gaza that the military said was being used as a "Hamas compound" killed at least 30 people, according to local health officials.

The overnight strike, which came after the military said it was launching new air and ground operations in central Gaza and and international medical group reported soaring casualties from strikes in the area.

The Al-Aqsa Martyrs Hospital in Deir al-Balah received at least 30 bodies from the strike on the school and another six from a separate strike on a home, according to hospital records and an Associated Press reporter at the hospital. Hamas-run media had earlier reported a higher toll from the strike on the school.

The Israeli military said Thursday its fighter jets struck the school run by the United Nations agency for Palestinian refugees, known by the acronym UNRWA. The Israeli military claimed, without immediately offering evidence, that Hamas and the Islamic Jihad used the school as cover for their operations.

UNRWA schools across Gaza have functioned as shelters since the start of the war, which has displaced most of the territory's population of 2.3 million Palestinians.

“Before the strike, a number of steps were taken to reduce the risk of harming uninvolved civilians during the strike, including conducting aerial surveillance, and additional intelligence information,” the Israeli military said.

Both strikes occurred in Nuseirat, one of several built-up refugee camps in Gaza dating back to the 1948 war surrounding Israel's creation, when hundreds of thousands of Palestinians fled or were driven from their homes in what became the new state.

The latest war began with Hamas’ Oct. 7 attack into Israel, in which militants killed some 1,200 people and took another 250 hostage. Israel's offensive has killed at least 36,000 Palestinians, according to Gaza's Health Ministry, which does not distinguish between fighters and civilians in its figures.

The military said Wednesday that forces were operating “both above and below ground” in eastern parts of Deir al-Balah and the Bureij refugee camp in central Gaza. It said the operation began with airstrikes on militant infrastructure, after which troops began a “targeted daylight operation” in both areas.

Doctors Without Borders said at least 70 bodies and 300 wounded people, mostly women and children, were brought to a hospital in central Gaza on Tuesday and Wednesday after a wave of Israeli strikes.

The international charity said Wednesday in a post on X that Al-Aqsa Martyrs Hospital in Deir al-Balah is struggling to treat “a huge influx of patients, many of them arriving with severe burns, shrapnel wounds, fractures, and other traumatic injuries.”

Israel has routinely launched airstrikes in all parts of Gaza since the start of the war and has carried out massive ground operations in the territory’s two largest cities, Gaza City and Khan Younis, that left much of them in ruins.

The military waged an offensive earlier this year for several weeks in Bureij and several other nearby refugee camps in central Gaza.

Troops pulled out of the Jabaliya camp in northern Gaza last Friday after weeks of fighting caused widespread destruction. First responders have recovered the bodies of 360 people, mostly women and children, killed during the battles.

Israel sent troops into Rafah last month in what it said was a limited incursion, but those forces are now operating in central parts of Gaza’s southernmost city. More than 1 million people have fled Rafah since the start of the operation, with many heading toward central Gaza.