Health Ministry spokesman Waheed Majroo says that dozens were also wounded in the attack on Tuesday in Gardez, the provincial capital. He says the city hospital reported receiving 130 wounded in the attack, which included a suicide bombing.
Hamza Aqmhal, a student at the Paktia University, told The Associated Press that he heard a very powerful blast. He says it shattered glass and broke all the windows at the building he was in. He says the university is about two kilometres from the training academy.
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Aqmhal says he was slightly injured by the glass.
Three officials said the provincial police chief and several of his staff were among the dead.
He says most of the casualties are civilians who had come to the centre, which also serves a government passport department.
The Taliban, seeking to reimpose strict Islamic law after their 2001 ouster by U.S.-led forces, claimed responsibility.