A school building where thousands of Palestinians had taken shelter was attacked by an Israeli air strike in Nuseirat in central Gaza.
According to local authorities in the Hamas-controlled strip, 16 people were killed.
The school, run by the UN's Palestine agency Unrwa, was used as a refuge for 7,000 refugees, according to the authorities in Gaza.
According to the Palestinian health organization Awda, a large number of injured, many of them children, were hospitalized after the air strike.
Israel's military says in a statement on Telegram that the attack was directed against terrorists who were hiding and operating there.
Nuseirat, which has functioned as a refugee camp for displaced Palestinians since 1948, has been the target of several large-scale Israeli attacks this summer.
A month ago, on June 6, 40 people were killed in an attack on a school in the same area, according to Hamas figures. There, too, thousands of refugees lived. The attack was condemned by, among others, UN Secretary-General António Guterres. The EU and the US have demanded transparent and independent investigations. According to Israel, nine terrorists were killed.
Two days later, on June 8, hundreds of Palestinians were killed in connection with the Israeli forces' liberation of four hostages held captive there.
On June 18, it was reported that at least 17 people were killed after a night of extensive bombing.
