Israel is calling 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.

Spokesman Mark Regev told the BBC Israel would apologise if it discovered that its fire was responsible for the strike on the school.

"We have a policy - we don't target civilians," he 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.

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 8 July. 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.
(BBC)