Hundreds of militants stormed military checkpoints in northwest Pakistan early Tuesday, killing at least eight soldiers and injuring 10 others, military and government officials said - the latest in a string of attacks against security forces.

Twenty-five militants died in the clash, according to the officials.

The predawn attack took place over several hours in Kurram, one of seven mostly ungoverned districts in Pakistan's tribal region along the Afghan border.

The district has seen a sharp increase in militant activity with insurgents who have fled military operations in neighboring South and North Waziristan.