ISLAMABAD 

At least six paramilitary troops and as many suspected militants who stormed a security forces’ compound in northwestern Pakistan were killed during an hours-long operation Tuesday, according to police and rescue officials.

Another 20 people, including security personnel, were injured, said local rescue department officials.

Suspected suicide bombers rammed an explosive-laden vehicle into the main gate of the compound, which serves as headquarters of the paramilitary force Frontier Constabulary in the Bannu district of northwestern Khyber Phaktunkhwa province, provincial police chief Zulfiqar Hameed told reporters, hours after security personnel began an operation against the attackers.

Jabhatu Ansar al-Mahdi Khorasan (JAMK), a little-known militant group affiliated with Tehreek-e-Taliban Pakistan (TTP), claimed responsibility for the attack, the broadcaster Hum News reported.

Hameed told reporters earlier that five attackers were killed and seven other people were injured in the operation.

According to the provincial rescue department, 18 security personnel and two civilians were transferred to a hospital.

A police officer told reporters earlier in the day that a powerful explosion was followed by heavy gunfire and several explosions.

Resident Karim Khan said parts of the vehicle were seen scattered along Kohat Road.

"We are near the spot, still hearing heavy firing and explosions in the area," he told Anadolu.