The latest reports say that the terrorists targeted the seminary children this time in Peshawar's Dir Colonny.
Police and rescue services reached there to shift the injured to nearby hospital.
The sources said many injured children were said to be in critical condition.
Security forces cordoned off the area and investigation was underway to determine the cause of the blast.
According to SSP Operations, an unknown man placed a red colored bag inside the seminary which caused explosion. He stated that 5-6 kg explosive material was used in the blast.
“This is highly condemnable act,” said KP CM Mahmood Khan who summoned a meeting to discuss the security situation in province.