The state-run Associated Press of Pakistan said the attacks targeted a religious school in Danda Darpakhel, near Miranshah, the tribal region's headquarters, killing at least six people and injuring 18 others.

Geo TV, quoting sources, put the death toll at 20. The report said the drone fired 10 guided missiles, which also targeted the home of the son of key Taliban commander Jalaluddin Haqqani.

It wasn't clear whether Haqqani's son was killed or injured. It was also not known if Haqqani, identified as a close aide of fugitive Taliban leader Mullah Omar, was in the area.

A BBC report said the area was later surrounded by militants.

The report said U.S. forces based in Afghanistan have been accused in recent days of stepping up attacks against suspected Taliban targets across the border in Pakistan's tribal areas.