Israel has decided to call up 16,000 extra reservists to bolster its military as the conflict in Gaza continues.

The deployment brings the total called up by Israel to 86,000. Officials told Israeli media the call-up gave the military “room to breathe”.

The move comes as Israel pledged to investigate a strike on a UN-run school that killed at least 16 people.

In all, more than 100 people in Gaza were killed on Wednesday, Palestinian officials said.

The US and UN condemned the attack, with UN Secretary General Ban Ki-moon calling it “unjustifiable”.

On Wednesday, Israel’s security cabinet met to approve the continuation of strikes against Palestinian militant group Hamas, which controls Gaza.

Israel has decided to call up 16,000 extra reservists to bolster its military as the conflict in Gaza continues

Operations would continue against suspected militants, suspected rocket sites and a network of tunnels discovered leading into Israel, the military said.

At least 19 air strikes were carried out overnight, officials said.

Israel began Operation Protective Edge on July 8. Since then at least 1,360 Palestinians have been killed. Most have been civilians.

Some 58 Israelis have been killed, 56 soldiers and two civilians. A Thai worker in Israel has also died.

The attack on the school in the Jabaliya refugee camp, which was sheltering more than 3,000 civilians, took place on Wednesday morning.

UN Secretary-General Ban Ki-moon said “all available evidence” suggested Israeli artillery was the cause.

The US state department also criticized the attack on the school. It also condemned those who hid weapons in UN facilities, a spokeswoman said.

Also on Wednesday, an attack on a market in Shejaiya killed 17 people, while an Israeli air strike killed seven people in Khan Younis, Palestinian officials said.

Those attacks came during a four-hour humanitarian ceasefire called by the Israelis after the school incident.

However, Israel said the truce was only partial. Hamas rejected it as meaningless.

Israel said Palestinian militants continued to fire rockets from Gaza, with more than 50 launched on Wednesday.

The current conflict, now in its 24th day, is the longest between Israel and militants from Gaza.

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