A Divvy bike was found Thursday submerged in Lake Michigan. View Full Caption Facebook/LeylaRuinsEverything

OAK STREET BEACH — Some of the mystery behind the submarine Divvy has been solved.

A photo of one of the rental bikes, seen underwater in Lake Michigan, gained some attention on Instagram.

Odd Obsession, a Bucktown video store, posted a photo of the Divvy bike Thursday morning after having spotted it on Leyla Ruins Everything's Facebook page.

Divvy commented on the post, hoping to track down the sunken bike.

"Would you mind emailing us at info@divvybikes.com w/ exact location so we can retrieve it? If so, happy to provide you free rides on us," they wrote. "Thank you!"

Around mid-day Thursday, Divvy spokesman Elliott Grenberger said the bike "was located at North Avenue beach, facing Oak Street beach" and was "recovered by our team on Tuesday."

Still no word on how it got there.

Let's go for a ride! A photo posted by Odd Obsession Movies (@odd.obsession.movies) on Jun 23, 2016 at 6:42am PDT

Logan Square bike mechanic John Davies shared the photo on Facebook, and came up with his own back story: "I have a picture in my head of a drunk tourist riding it right into the lake. I think it's kind of hilarious!"

A friend of Davies added: "In Chicago, even the bikes sleep with the fishes ..."

The bike share system charges its users a $1,200 fine for lost or stolen bikes.

UPDATE: The photo was originally posted by LeylaRuinsEverything on Facebook and then it was reposted on Instagram by Odd Obsession Movies.

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