PESHAWAR, Pakistan (AP) — A suicide bomber and several gunmen detonated an explosives-laden vehicle near a security post in northwest Pakistan late Saturday, triggering an intense firefight that killed at least three police officers, police said.

The attack took place in Bannu, a district in Khyber Pakhtunkhwa province bordering Afghanistan, police official Zahid Khan said. He said multiple explosions were heard shortly after the attack and that several nearby houses and the security post collapsed from the impact of the blast.

He provided no further details, saying the exchange of fire was ongoing and that some officers were believed to be wounded and trapped under the rubble.

No group immediately claimed responsibility.

However, suspicion is likely to fall on the Pakistani Taliban, known as Tehrik-e-Taliban Pakistan, or TTP, and allied militant groups that have carried out similar attacks in the past. Pakistan has witnessed a surge in militant violence in recent years.

The TTP is a separate group but allied to the Afghan Taliban, who seized power in Afghanistan in 2021.