ISRAEL made the extraordinary suggestion today that it would observe a four-hour lull in fighting in Gaza — except where its soldiers were operating.

The army said it agreed to a humanitarian pause, but insisted it would not apply in areas where it was “currently operating” and warned Palestinians who had fled their homes not to return.

Following the offer, however, health officials reported that 15 people had been killed and 150 wounded in an Israeli airstrike on a crowded shopping centre in Shijaiyah.

They said that residents had ventured out because they believed a ceasefire to be underway.

The offer of the pause came just hours after Israeli shells slammed into a UN school in the Jebaliya refugee camp in Gaza where more than 3,000 people had sought shelter, killing at least 16 of them.

It was the second time in a week that a UN school had been hit, drawing furious denunciation from the head of the UN agency for Palestinian refugees, UNRWA.

“I condemn in the strongest possible terms this serious violation of international law by Israeli forces,” said UNRWA Commissioner General Pierre Krahenbuhl, adding that the school’s location had been communicated to the Israeli army 17 times.

“No words adequately express my anger and indignation,” he wrote on his official Twitter account, saying that 3,300 people had been sheltering there.

“I call on the international community to take deliberate international political action to put an immediate end to the continuing carnage.”

UNRWA Gaza director Bob Turner said the UN was “confident” Israel was responsible.

He said UN workers had collected projectile fragments that suggested they were from artillery shells fired from Israeli positions north-east of the school.

And agency spokesman Abu Hasna said the international community must step in.

“It’s the responsibility of the world to tell us what we shall do with more than 200,000 people inside our schools, thinking the UN flag will protect them,” he said. 

“This incident proves that no place is safe in Gaza.”

Over 1,300 Palestinians have now died and upwards of 7,100 have been wounded — 2,164 children and 282 elderly people.

UN figures show up to 240,000 people have fled their homes in a territory which holds 1.7 million, leaving one in seven homeless.