After another night of deadly fighting in Gaza during which 16 people were killed when Israel shelled a UN school, Communications Minister Malcolm Turnbull told ABC radio that Israel had a right to defend itself.

More than 3,000 people had been sheltering at the Abu Hussein School when the dawn attack happened. Palestinian officials said several Israeli tank shells struck the school. The bombing, in Gaza’s Jabaliya refugee camp, came hours after Gaza’s only power station was destroyed.

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“Well, Israel risks extinction, Israel faces an existential threat every day … Israel can barely afford to lose a battle let alone a war,” Mr Turnbull said.

“As long as Hamas is firing rockets into Israel, the Israeli Defence Force has to defend its own population. I mean that’s what we’d expect the Australian Army to do for us,” he said.

The United Nations expressed strong disapproval of the attack.

UN Secretary General Ban Ki-moon condemned the strike as “unjustifiable,” calling for those responsible to be held to account.

“This morning, a UN school sheltering thousands of Palestinian families suffered a reprehensible attack,” Ban said during a visit to Costa Rica on Wednesday.

“It is unjustifiable, and demands accountability and justice.”

It is the second time in a week that a UN school housing refugees has been hit. Ban accused the Israeli military of ignoring repeated communications on the location of the school.

“I want to make it clear that the exact location of this elementary school has been communicated to the Israeli military authorities 17 times, as recently as last night, just a few hours before this attack,” he said.

“They are aware of the coordinates and exact location of where these people are.”

Mr Turnbull, who has a large Jewish constituency in his Eastern Sydney electorate of Wentworth, says no-one is comfortable with the situation at the moment, “least of all Jews in Australia.”

“Jews in my electorate are anguished by this,” he said.

But he says Israel has to defend itself from any rockets fired by Hamas.

“As long as Hamas is firing rockets into Israel the Israeli Defence Force has to defend its own population,” he said.

Prime Minister Tony Abbott says he accepts Israel is under attack from rocket attacks from Gaza but he says there should be an immediate ceasefire.

“Plainly too many people are dying. It is just wrong what is happening,” he told Fairfax Radio.

-with ABC