Medical staff and Hamas-run health ministry said at least 33 Palestinians were killed in two crowded restaurants and markets, and dozens of Israeli strikes were injured.

Graphic video posted on social media shows a body falling on a table in a Thai restaurant in the northern rimal community, which also runs as a community kitchen.

Video from a nearby market showed a child with a backpack dying on the street.

The Israeli military said it was investigating the report.

Earlier, the hospital said at least 59 people have been killed in the attack since Tuesday night, most of whom serve as shelter for displaced families in two schools.

The strike is what Israel says is preparing to strengthen and expand the military campaign against Hamas 19 months later.

Two strikes on Al-Wahda Street, Rimal, one of Gaza's busiest commercial hubs, happened almost simultaneously on Wednesday afternoon, about 100m (330 feet) apart.

Shortly afterwards, footage from the scene showed the injured person being transported on a chair and on the back of a car.

A woman held the baby on her arm and told Reuters that they were in a Thai restaurant at the time of the attack.

"Everyone is dead," she said. "Blood is like a lake, oh, my baby, blood."

Photos shared by local activists were not immediately verified, showing many bodies. They appear to include a boy selling coffee, two parents and their young son, and a market vendor sitting at his small stall.

Colleagues said Palestinian journalist Yahya Sobeih was also killed.

In another video, Abu Saleh Abdu, owner of the nearby Palmyra restaurant, said many children, elderly and passers-by were killed.

He asked in his speech to the Israeli army: "What do you want to achieve? You haven't bombed any fighter planes or any weapons. You've only hit civilians."

Thai restaurants were destroyed during Israeli ground operations last year, but have recently been rebuilt with tents and temporary structures.

In addition to selling basic meals, the restaurant prepares hundreds of hot meals a day for humanitarian organizations to distribute to poor and displaced people.

The Hamas Government Media Office in Gaza accused the Israeli military of committing war crimes in four separate incidents within 24 hours.

Women and children are 33 out of 33, whose unoperated Abu Humeisa school in the Bureij refugee camp in central Gaza was bombed twice on Tuesday, according to a civil defense agency operated by Hamas.

Witness Ali al-Shaqra said Wednesday that 300 families have been living in schools and the impact of the strike was like an "earthquake."

The Israeli military said it hit “terrorists working in the Hamas command and control center.”

The military has not commented on a strike on the Karama school near Tuffah in eastern Gaza City on Wednesday morning, with the Civil Defense saying 15 more people were present.

This is amid international condemnation of Israel's plans to expand and strengthen the ground offensive against Hamas.

Israeli officials said they included seizing all territories indefinitely, forcibly relocating Palestinians to the south and taking over aid with private companies despite protests from the United Nations and its humanitarian partners.

Prime Minister Benjamin Netanyahu said on Monday that his security cabinet had decided to take "strong action" to destroy Hamas and rescue its remaining hostages. He said Gaza's 2.1 million people "will be moved to protect it" and the troops "will not enter and come out".

Israel cut off all supplies from Gaza on March 2 and resumed its offense two weeks after the two-week ceasefire collapse, saying it was putting pressure on Hamas to release its remaining 59 hostages.

According to the United Nations, new strikes and ground operations have already resulted in hundreds of casualties, with an estimated 423,000 displaced, and about 70% of Gaza people are in Israeli evacuation orders, in an Israeli-designed "go-free" area, or both in Israeli evacuation orders.

Aid agencies also warn that mass hunger is coming unless the lockdown is over.

The United Nations has stated that under international law, Israel has an obligation to ensure food and medical supplies for Gaza's population. Israel said it complies with international law and has no shortage of aid as thousands of truck loads entered Gaza during the ceasefire.

Prime Minister of Palestinian authorities based in the occupied West Bank Mohammad Mustafa told the BBC that the situation in Gaza was a "real disaster."

"This can't continue. It's a siege, a famine. There's no water, no electricity, no hope."

Mustafa urged the international community to step up efforts to hold a new ceasefire and hostage release agreement between Israel and Hamas as soon as possible, warning: "People are dying in Gaza every day and this will not happen again."

An Israeli official said Monday that the expanded offense did not begin until U.S. President Donald Trump visits the region next week, providing Hamas with what he called a "window of opportunity" to agree to a deal.

But Bassem Naim, a senior Hamas official, said Tuesday that the negotiations did not have “no sense” and that Israel continued what he called the “war of hunger.”

The Israeli military launched a campaign to destroy Hamas in response to the unprecedented cross-border attack on October 7, 2023, with about 1,200 people killed and another 251 were taken hostage.

According to the region's Ministry of Health, at least 52,653 people have been killed in Gaza since the Israeli offensive resumed, including 2,545.