An Israeli attack on a school used to shelter displaced Palestinians has killed at least 15 people in central Gaza, officials say.

Gaza’s Hamas-run Civil Defence Agency said the site in Nuseirat camp was struck by a volley of artillery on Sunday, killing entire families and wounding dozens more.

The Israel Defence Forces (IDF) said it was looking into the reports.

Earlier, five children were reportedly killed by a drone strike while playing on a street corner in northern Gaza.

A civil defence spokesman said the attack on al-Mufti school, where hundreds of displaced people from around Gaza were sheltering, had injured at least 50 people and more than a dozen were killed.

The main areas of conflict in Gaza in recent days have been in the north, where Israeli forces have been intensifying attacks for over a week as part of a major ground operation. Hundreds have since been killed, Gazan authorities have reported.

Residents of Beit Hanoun, Jabalia and Beit Lahiya have reported being cut off from nearby Gaza City, while Israeli tanks have been seen on the outskirts of the territory’s largest city.

Hospitals in the area are running out of supplies, although the World Health Organisation said a joint operation with the Red Cross had resupplied two of them -after nine days of attempts.

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The five children in northern Gaza were reportedly killed in an Israeli air strike while playing on a street corner in al-Shati camp.

Graphic images from the scene in the aftermath show the bloodied bodies of what appeared to be young teenage boys.

One of them looked to be clutching several glass marbles in his hand.

According to a report from the scene, told to a BBC correspondent, a drone strike hit a person walking down the street, which killed the children and injured seven other people.

Later images showed the bodies of the five boys wrapped in white shrouds and laid out on the floor side-by-side.

An aunt of one of the boys, named Rami, wrote a moving tribute to him on social media. She said the family had moved to al-Shati after being forced to leave their homes in Jabalia to a “safer area” because of the war.

The IDF has not yet responded to questions about the incident.

Over the last year of war, the Hamas-run health ministry has reported more than 42,000 people killed.

About 1.9 million of Gaza’s 2.4 million people have been displaced by the war – many of whom have been forced to move multiple times to escape.

The fighting began after Hamas launched an unprecedented attack on northern Israel on 7 October last year – killing about 1,200 people in northern Israel and taking more than 200 hostage in Gaza.