The victim's family reported him missing on Friday, before members reported smelling something "really awful" as they neared the tanning rooms.
An Indiana man was found dead inside the tanning bed at a Planet Fitness, three full days after he allegedly entered the gym.
Victim 39-year-old Derek Sink was identified by the Marion County Coroner's Office on Tuesday, per Indy Star; no cause of death has been determined.
The startling discovery was made Monday morning, as police were called to an Indianapolis location around 8:30am. According to gym member Elizabeth Len, who spoke with WTHR, she noticed something smelled "really awful" when she arrived that morning -- saying the odor grew stronger closer to the tanning rooms.
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View StoryThe victim's family also told the outlet that Sick went into the tanning bed Friday, the same day they reported him missing. His aunt told WTHR her nephew was wearing an ankle monitor, which helped authorities realize he never left the gym.
Per family members, Sink had issues with substance abuse and a needle was found in the room with him.
"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," Planet Fitness Chief Corporate Affairs Officer McCall Gosselin said in a statement.
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View Story"At Planet Fitness, we have robust operational brand protocols in place, as the safety and well-being of our members is our top priority," Gosselin added. "We are working closely with our local franchisee to ensure they are upholding those brand protocols."
The gym was reportedly open over the weekend, from 7am-7pm on both Saturday and Sunday.
"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?" gym member Len asked.
The victim's family, meanwhile, hope more policies are put in place to prevent something similar happening again -- like check-lists for staffs and stronger cleaning policies.