Actually, any dual use facility is a target, plain and simple. Using civilian cover is illegal.
What are you talking about? There has been no proof of any instance of Hamas using human shields. BBC chief editor mentioned this.
If you're trying to justify this attack, here is what the UN has to say about it:
UN Chief: Israeli attack on Gaza school 'unjustifiable' | Maan News Agency
SAN JOSE (AFP) -- UN Secretary General Ban Ki-moon condemned an Israeli strike on a Gaza school that killed 16 people as "unjustifiable" Wednesday, 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.
"It is unjustifiable, and demands accountability and justice."
The school in the Jabaliya refugee camp in northern Gaza, which was sheltering more than 3,000 homeless people, came under attack from Israeli tank shells at dawn Wednesday.
It is the second time in a week that a UN school housing refugees has been hit, and the sixth in two weeks.
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.
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Actually, he's right on that one. The area was not covered by the ceasefire, though that doesn't excuse Israel for the bombing.
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I haven't seen a source for that. But, even so, doesn't justify artillery bombing on a market. The ground combat was further east.