At least 31 people, including 16 police officers, have been killed and more than 100 others injured in a suicide bombing and armed attack on police headquarters in Kohat, northern Pakistan, AFP reported, citing a senior police official.

According to police officials, an exchange of fire and a clearance operation are still underway inside the compound, as several militants have barricaded themselves inside a building belonging to a special police unit.

“Several militants are still barricaded inside the special police unit building. Their exact number is unknown,” an official told AFP on condition of anonymity.