Israel calls up 16,000 reservists, vows to investigate strike on UN school in Gaza

Israel's military announced Thursday that it had called up 16,000 reservists to potentially join its ongoing offensive against Hamas militants in Gaza. 
The call-up, which brings the total number of troops called up by Israel to 86,000, could signal a potential widening of Operation Protective Edge, which began July 8 as an effort to halt rocket attacks by Hamas against southern Israel and destroy tunnels used by Hamas militants to cross from Gaza into Israel for the purpose of attacking soldiers and civilians. 
A lasting cease-fire in the region appears no nearer. The Associated Press reported that Egyptian officials met Wednesday with an Israeli envoy about Israel's conditions for a cease-fire, including disarming Hamas, according to a high-ranking Egyptian security official. The official spoke on condition of anonymity because he was not allowed to discuss the delicate diplomatic efforts.
The Times of Israel reported that Egypt is refusing to host a Palestinian delegation unless Hamas ceases fire. For its part, Hamas has said it will only halt fire once it receives guarantees that a seven-year-old Gaza border blockade by Israel and Egypt will be lifted. Meanwhile, The Times of Israel reported that Israeli's Security Cabinet met Wednesday and approved ongoing strikes against Hamas. 
The troop announcement also came as Israel's military said it would investigate whether tank shells struck a United Nations-run school in a Gaza refugee camp, an event that drew condemnation from the U.S. and the U.N. Israeli government spokesman Mark Regev told the BBC that Israel would issue an apology if it determined that fire from its troops struck the school. 
"We have a policy; we don't target civilians," Regev told the BBC, before adding "It's not clear to us that it was our fire, but we know for a fact there was hostile fire on our people from the vicinity of the school."
Pierre Kraehenbuehl, chief of the U.N. aid agency for Palestinian refugees, told the Associated Press that Israel must try harder to ensure that civilians are not hurt, especially in Gaza, where 1.7 million people are squeezed into a small coastal territory. His agency has opened 80 of its schools to more than 200,000 Palestinians fleeing the violence.
"What maybe the world forgets ... is that the people of Gaza have nowhere to go," he said. "So when the fighting starts and they move, it is not as if they can cross a border to somewhere." 
Israel has accused Hamas of using residents of Gaza as human shields by launching rockets from the territory's most densely populated cities. 
U.N. Secretary-General Ban Ki-moon, using somewhat less diplomatic language that Kraehenbuehl, called the school shelling "outrageous" and "unjustifiable," and demanded an immediate humanitarian cease-fire, adding, "Nothing is more shameful than attacking sleeping children."
Gaza health authorities say at least 16 people were killed in the school attack and 1,360 Palestinians have been killed since the start of the offensive, though it is unclear how many were civilians and how many were Hamas militants. 56 Israeli soldiers have died since the start of the offensive, as well as two Israeli civilians and a Thai worker.  
On Wednesday, White House spokesman Eric Schutlz told reporters the Obama administration expected a "full, prompt, and thorough investigation" into the shelling, but stopped short of directly blaming Israel. 
"We are extremely concerned that the thousands of internally displaced Palestinians, who have been called on by the Israeli military to evacuate their homes, are not safe in these UN-designated shelters in Gaza," Schultz told reporters. "We also condemn those responsible for hiding weapons in the United Nations facilities in Gaza. All of these actions violate the international understanding of the UN’s neutrality."
At the State Department, spokeswoman Marie Harf described a purported leaked transcript of a weekend call between President Obama and Israeli Prime Minister Benjamin Netanyahu as "complete crap," claiming that the intention of the leak to hurt the U.S.-Israeli relationship.
"I don't know toward what end. I don't know who did it," she said. "But I don't know what other conclusion you can draw from that." Both the U.S. and Israeli government deny the authenticity of the transcript, which came amid stinging reports in some Israeli media outlets accusing Kerry of aligning himself too closely to Hamas and being dismissive of Israeli complaints.