The strike, which had the support of Afghan troops, was launched Sunday on a compound that also contained a mosque and a madrassa, or Islamic school, in the Zarghun Shah district of Paktika province, a coalition statement said.
"Coalition forces confirmed the presence of nefarious activity occurring at the site before getting approval to conduct an air strike on the location," the statement said.
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Early reports said seven children at the school were killed in the strike and that "several militants" also were killed, the coalition statement said. Two suspected militants also were detained.
"We are saddened by the innocent lives that were lost as a result of militants' cowardice," Maj. Chris Belcher, a coalition spokesman, said in a statement. "This is another example of Al Qaeda using the protective status of a mosque, as well as innocent civilians, to shield themselves."
Coalition troops had "surveillance on the compound all day and saw no indications there were children inside the building," Belcher said. He accused the militants of not letting the children leave the compound that was targeted.
"If we knew that there were children inside the building, there was no way that that airstrike would have occurred," said Sgt. 1st Class Dean Welch, another coalition spokesman.
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