Indianapolis police are investigating the death of a man found dead in a tanning bed at a Planet Fitness gym Monday morning.

The man was identified as Derek Sink, 39, by the Marion County Coroner’s Office. 

Sink had went into a tanning bed on Friday, his family told NBC affiliate WTHR of Indianapolis. 

When he failed to come home, his family reported him missing. His aunt said that Sink was wearing an ankle monitor which led investigators to determine he never left the gym. He was ultimately located in the tanning bed at the gym, located in the 8000 block of Hardegan Street, on Monday morning. 

Family said that Sink had struggled with drugs and a needle was found in the room with him. 

Marion Superior Court records show Sink had been charged with possession of a narcotic drug and possession of a controlled substance last year. In a plea agreement to the first charge, he was sentenced to one year of home detention including drug testing, which started in May.

It’s not clear how Sink went unnoticed for so long.

The coroner’s office has not yet determined a cause or manner of death as of Wednesday morning.  Indianapolis Metro Police says the death investigation is ongoing.

Elizabeth Len was at that Planet Fitness Monday morning before law enforcement discovered Sink.

She said that she and other members noticed a bad smell in the building near the tanning rooms. “The tanning bed has a door, I believe, but still, why are we not concerned that the tanning bed has been closed for three days, potentially?” Len said to WTHR.

Planet Fitness’ Chief Corporate Affairs Officer McCall Gosselin said in a statement: “We were deeply saddened by the passing of one of our members, and the franchise owner is working with the local authorities in their investigation.”

“At Planet Fitness, we have robust operational brand protocols in place, as the safety and well-being of our members is our top priority. We are working closely with our local franchisee to ensure they are upholding those brand protocols,” Gosselin added.