Police say there were two explosions inside a counterterrorism police station in Kabal, northwest Pakistan.

Two explosions rocked a counterterrorism office in northwest Pakistan on Monday, killing at least eight people, police said, and several others were injured.

Provincial police chief Akhtar Hayat said it was not clear yet what caused the explosions in northwestern Swat valley.

Hayat said there was an old ammunition store in the office, and police were probing whether that caused the explosions or if it was a militant attack. No one has so far claimed responsibility.

Hayat said most of those killed were police counterterrorism officers.

“The reports indicate that the roof of the counterterrorism department facility … caved in. Eight dead have been accounted for. The rescue effort is continuing. They are trying to remove the rubble,” said Al Jazeera’s Kamal Hyder on Monday.

More to follow.