LAHORE, Pakistan (CNN) -- Police raided an Islamic school and arrested seven students hours after a blast in a mosque in northern Pakistan left at least 50 dead and dozens injured, according to an Associated Press report. A man, right, mourns the death of his two sons in a suicide attack near Peshawar that killed at least 50. A bomb, packed with ball-bearings and nails, tore through Eid prayers at a mosque packed with hundreds of worshippers northeast of Peshawar on Friday, targeting Aftab Ahmad Khan Sherpao, former Pakistani interior minister, local police told CNN. The blast left blood-stained clothes, hats and shoes as well as body parts and pieces of flesh scattered across the mosque, according to reports.
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Bomb detonated at mosque northeast of Peshawar, Pakistan
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Local police: At least 50 dead in attack on Eid prayers
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Reports: Former interior minister was target, escapes blast, one son injured
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Minister supervised military operations in tribal areas against militants
The president -- who survived two assassination attempts in December 2003 -- denounced Friday's attack, speaking out against what he said was a small number of Muslim extremists who would carry out such an act, according to a report from the state-run Associated Press of @placeholder.