The head of the UN agency for Palestinian refugees expressed "shock and disbelief" over the shelling of another UN school in Gaza Sunday that killed at least 10 people.
The attack in the southern city of Rafah marked the third time in 10 days that a UN school has been hit, including the Israeli shelling four days ago of a school in Jabaliyah that killed 16 people.
Pierre Krahenbuhl, head of the UN Palestinian refugee relief agency, UNRWA, said the shell exploded just outside the main gates of the school in Rafah, causing multiple deaths and injuries inside and outside the building.
"Coming in the aftermath of a series of incidents, of shelling incidents in recent weeks and most recently the shelling of our school in Jabaliya, which provoked an outcry and was clearly and deservedly condemned by UNRWA and myself publicly, this is of course another incident that generates both shock and disbelief at the fact that it can happen again," he said on CBS's Face the Nation.
Krahenbuhl said about 3,000 people had taken shelter in the school.
It was not immediately known whose forces were responsible for the latest incident.
Israel accuses Hamas, the Islamist group that rules Gaza, of using civilians as shields by locating weapons and command centers in or near civilian structures.
Krahenbuhl acknowledged that on three occasions inspections had turned up weapons caches in UN premises.
"But clearly, nobody can suggest that because weapons are found in one premise that it can be in any sense a justification for shelling other schools and endangering the lives of displaced people in the middle of a war zone," he said.
Having seen the extent of the deaths and damage caused, he said, "there is no doubt in my mind whatsoever that insufficient measures of precaution and control and protection are being taken, including by the Israeli Defense Force, when engaging in Gaza."
In Gaza, 1,766 Palestinians have been killed and another 9,320 wounded since the start of the Israeli offensive on July 8.
Figures released by the UN humanitarian agency OCHA on August 2 gave a total of 1,525 dead.
Of the 1,196 killed whose identities could be verified, 1,033 were civilians, nearly 84 percent, OCHA said. The number includes 329 children and 187 women.
Of the Palestinians killed, 191 were members of armed groups. On the other side, 66 Israelis have been killed, including 64 soldiers, all of whom have died since the ground offensive began.
* This story was edited by Ahram Online.