PESHAWAR, Pakistan (AP) — Several Pakistani Taliban detainees overpowered their guards at a counter-terrorism center in northwestern Pakistan overnight, snatching police weapons, taking hostages and seizing control of the facility, officials said Monday.

The incident erupted late Sunday and quickly evolved into a standoff. Pakistani officials later confirmed that one counter-terrorism officer was killed during the takeover at the detention center in Bannu, a district in the Khyber Pakhtunkhwa province and part of a former tribal region.

Police and the military scrambled to deploy troops and special forces to the area but by Monday evening, some 20 hours later, the hostage crisis was still ongoing. According to officials, at least 30 Taliban fighters were involved in the takeover and there were possibly as many as 10 hostages.

The brazen action reflected the government’s inability to exercise control over the remote region along the border with Afghanistan. The Pakistani Taliban are a separate group but also allied with the Afghan Taliban, who seized power in the neighboring country last year as U.S. and NATO troops were in the final stages of their pullout from Afghanistan.

Few other details emerged about the takeover, which apparently happened while police were interrogating the Taliban detainees, according to Mohammad Ali Saif, a spokesman for the provincial government. 

Saif said the place was surrounded and that officials were trying to negotiate with the hostage-takers. However, he said the “government will not accept any demands of the terrorists” who were being asked by authorities to surrender. Saif earlier said an operation was underway but did not elaborate.

Authorities enlisted the help of several relatives of the Taliban insurgents in the negotiations, several security officials told The Associated Press. They spoke on condition of anonymity because they were not authorized to talk to reporters. They said some Pakistani clerics were also in talks with the leadership of the Pakistani Taliban in neighboring Afghanistan to resolve the hostage crisis in a peaceful manner.

The officials said some soldiers were also among the hostages. There were concerns that the military could storm the facility if negotiations fail. In a video message circulating on social media, the hostage-takers threatened to kill the officers if their safe passage was not arranged.

Mohammad Khurasani, a spokesman for the Pakistani Taliban — also known as Tehreek-e-Taliban Pakistan or TTP — said some of the hostage-takers were TTP members who had been detained for years in Bannu.

Khurasani said the TTP fighters were demanding safe passage to North or South Waziristan, areas that were a Taliban stronghold until a wave of military offensives over the past years drove out many of the insurgents.