This one has authorities scratching their heads. A man who was reported missing was eventually found three days later, deceased inside a Planet Fitness tanning bed.

Here's what we know. The deceased man, 39-year-old Derek E. Sink, was last seen on Friday, Nov. 8, by family members and reported missing on Sunday, Nov. 10.

Apparently, Sink had gone into the Planet Fitness in Indianapolis on Friday and never exited the location. Police know that he never exited the location because Sink was on probation and had an ankle monitor on.

They were able to track his location after he was reported missing to see he was at the gym and had been for days.

During the same time period, members of the gym and employees started to notice a foul smell that was coming from the tanning bed area of the gym. That's when it was discovered that Sink was in a closed tanning bed, deceased.

Sink struggled with addiction, and there was a needle found in the tanning booth room where he died.

One of the members of the gym who noticed the foul smell, Elizabeth Len, commented to WTHR-TV, wondering how something like this could happen.

"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?" she asked.

McCall Gosselin, Chief Corporate Affairs Officer at Planet Fitness, released this statement on behalf of the business:

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.

One might assume that they aren't working hard enough at it, as nobody checked this tanning bed for three days.

Sink's family said they hope that Planet Fitness establishes some sort of nightly checklist that involves double-checking the tanning beds daily or nightly.

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