A Gaza health official says 10 people have been killed by a strike near a United Nations school in the embattled coastal territory.
Ashraf al-Kidra says another 35 were wounded after the hit near a boys' school in the southern town of Rafah that is sheltering people displaced by the 27-day conflict between Israel and Hamas.
Witnesses said the attack happened while people were waiting in line for food supplies.
It was hit in what appeared to be an Israeli airstrike today.
The Israeli military had no immediate comment.
U-N Secretary-General Ban Ki-moon says the attack is a "moral outrage and a criminal act.''
He calls it another gross violation of international humanitarian law.
A spokesman says the Israeli military is scaling down its presence in some parts of Gaza as it begins a "new phase'' in its operation aimed at stopping rocket fire toward Israel.
In nearly four weeks of fighting, more than 1,700 Palestinians, mainly civilians, have been killed as well as nearly 70 Israelis, almost all soldiers.