Israel is calling up 16 thousand army reservists - in a move which gives them the ability to significantly expand their offensive on Gaza.
The United Nations says the carnage must stop after an attack by Israeli forces killed at least 16 Palestinians sheltering in a U.N. run school in Gaza.
The Israeli army says it's investigating the incident - but insists it only responded after Hamas militants fired from near the building.
The US has condemned the attack, and Chris Gunness, who works for the United Nations, is accusing Israel of violating international law:
