The preferred candidate to be a county fire chief is under investigation by the police watchdog, it has emerged.
As first reported in the NN Journal, the inquiry relates to Nikki Watson's previous post with Avon and Somerset Police.
Ms Watson was selected as the preferred candidate after a two-day interview process.
She was due to attend a panel confirmation hearing in December, but pulled out at the last minute.
The role of Chief Fire Officer became vacant when Nikki Marzec, who had been selected for the post on an interim basis, stepped down after just ten days following speculation about her relationship with the Police, Fire and Crime Commissioner (PFCC) Stephen Mold
The PFCC's office told the BBC that Ms Watson became the preferred candidate after an "open and rigorous" two-day interview process.
According to the NN Journal, a complaint about her is being investigated by the Independent Office for Police Conduct (IOPC).
The IOPC will not confirm the identity of the person they are investigating but said: "We can confirm we are investigating the conduct of a former senior Avon and Somerset Police officer regarding their attendance at a policing conference in 2023 and whether proper policies and procedures were followed.
"Our investigation, which is well advanced, followed a referral from the force in October 2023."
The PFCC's office said: "Nikki Watson has made us aware of an issue relating to her previous role in Avon and Somerset Police, which arose after she had been named as preferred candidate for the role of Chief Fire Officer.
"We are confident that the IOPC will be carrying out a full, thorough and independent investigation of the matter, and that they will be doing that as quickly as possible.
"The confirmation process will continue, pending the outcome of the IOPC investigation, and we look forward to briefing the Panel fully on February 20."
The Fire Brigades Union representative for the East Midlands, Adam Taylor, said:
"The PFCC has once again failed to act with the integrity and transparency required of those leading our fire service.
"Firefighters and the public had been given no adequate explanation for the delay in the appointment since December. It appears that even the panel overseeing the process had been kept in the dark.
"While PFCC Mold refuses to step down, Northamptonshire Fire and Rescue Service faces an escalating crisis in senior leadership."