ISLAMABAD, April 25 (Aljazeera) - Two explosions have rocked a counterterrorism facility in northwest Pakistan, killing at least 12 people and injuring more than 50 others, police said.

Sharifullah Khan, a police official in Kabal, told Al Jazeera that at least 12 people died in the blasts on Monday at the Counter-Terrorism Department (CTD) in Khyber Pakhtunkhwa province’s Swat Valley while more than 50 were reported injured.

He added that he doesn’t believe the blasts were caused by “terrorism”. The “explosions occurred after explosive material in the CTD building’s basement caught fire”, he said.

The building complex also houses the Kabal district police station and headquarters of a reserve police force, but the main damage was done at the counterterrorism department building.

Provincial police chief Akhtar Hayat said there was an old ammunition store in the office, and police were probing whether that caused the explosions or if it was an attack.

Two attacks on large police bases have been linked to the Pakistani Taliban, known as Tehreek-e-Taliban Pakistan (TTP) since the start of the year.

Most of those killed on Monday were police counterterrorism officers, Hayat said, adding that a woman and her child who were passing by the building were also killed.

Bilal Faizi, spokesman for Khyber Pakhtunkhwa’s provincial rescue service, said the search for more wounded was still in its initial stages.

The regional hospital administration said it received several wounded people, some of them in critical condition.