Police have said the deadly blasts that struck a counter-terrorism facility in the north west of Pakistan were caused by an electrical fault and not a terror attack.

The short circuits occurred on Monday at a munitions warehouse inside the centre in Swat, a district in Khyber Pakhtunkhwa province bordering Afghanistan.

Nine officers, two civilians and five recently detained militants were killed.

More than 50 people, mostly police officers, were wounded when the short circuits ignited explosions, seconds apart, according to Akhtar Hayat, the provincial police chief.

Initially, police said it could be an act of terrorism but an investigation later concluded that short circuits caused the explosions, according to a police statement released on Tuesday.

Nasir Mahmood Satti, a district police chief, also confirmed there was no attack from the outside.

Police and government officials attended a collective funeral ceremony on Tuesday for the officers killed in the blasts.

Associated Press images from the scene showed destroyed cars and fallen trees at the facility, which also houses a police station and the headquarters of a reserve police force.

The district of Swat lies at the centre of the picturesque Swat Valley, once the stronghold of the Pakistani Taliban.

The military carried out a massive operation there in 2007 and later claimed to have routed the militants and restored normality. However, attacks have persisted.

Separately, the Pakistani Taliban — also known as Tehreek-e-Taliban Pakistan or TTP — said their fighters attacked a security checkpoint on the outskirts of Peshawar, the provincial capital, on Monday night. There was no confirmation of any attack from the authorities.

The Pakistani Taliban are separate but allied with the Afghan Taliban, who seized power in neighbouring Afghanistan in August 2021. The takeover has emboldened the TTP, which has stepped up attacks in recent months.