A Greater Manchester Fire and Rescue Service firefighter was suspended after an X-rated photo appeared online.
Officials told BBC that the firefighter admitted that he invited women into the fire station, but denies that he's the one who appears in the photo of a couple having sex inside a fire apparatus.
Assistant County Fire Officer Geoff Harris launched an investigation into the photos in June, according to BBC.
"We are continuing to investigate the circumstances of an incident that appeared in the national media in June," the fire brigade said in a statement. "A full report will be prepared at the conclusion of the investigation."
When the photos appeared, a spokeswoman said, "I cannot believe we're still seeing highly inappropriate images like this on the fire service in 2017. It's not who we are."
"Crews will be embarrassed by this at best. Most people will be furious at the suggestion this is acceptable behaviour or a reflection of how we behave. It isn't."