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Official: 13 killed as shells hit Gaza UN school

Smoke and fire from the explosion of an Israeli strike rises over Gaza City, Tuesday, July 29, 2014. Israel escalated its military campaign against Hamas on Tuesday, striking symbols of the group's control in Gaza and firing tank shells that shut down the strip's only power plant in the heaviest bombardment in the fighting so far. The plant’s shutdown was bound to lead to further serious disruptions of the flow of electricity and water to Gaza’s 1.7 million people.(AP Photo/Hatem Moussa) Smoke and fire from the explosion of an Israeli strike rises over Gaza City, Tuesday, July 29, 2014. Israel escalated its military campaign against Hamas on Tuesday, striking symbols of the group's control in Gaza and firing tank shells that shut down the strip's only power plant in the heaviest bombardment in the fighting so far. The plant’s shutdown was bound to lead to further serious disruptions of the flow of electricity and water to Gaza’s 1.7 million people.(AP Photo/Hatem Moussa)

By Associated Press July 30, 2014 1 min read

GAZA CITY, Gaza Strip (AP) – At least 13 people were killed early Wednesday after tank shells hit a U.N. school in Gaza where hundreds of Palestinians had taken refuge from Israeli attacks.

Gaza health official Ashraf al-Kidra said another 90 Palestinians were wounded in the shelling.

Adnan Abu Hasna, a spokesman for a U.N. aid agency, says tank shells hit the Abu Hussein U.N. school in the Jabaliya refugee camp around 4:30 a.m.

An AP reporter who arrived later at the school saw a large round hole in the ceiling of one classroom and in one of the bathrooms. In another classroom, the strike had blown out the front wall.

The incident comes a day after Israel unleashed its heaviest air and artillery assault in the bloodiest day of the three-week Gaza war, destroying key symbols of Hamas control and shutting down the territory’s only power plant.