A Gimli business owner says sending a friend request to the person who allegedly stole from his store this week is all it took to convince a young man to turn himself in.

Stefan Tergesen, owner of H.P. Tergesen's in Gimli, posted surveillance footage of the theft in his shop on Facebook on Friday.

"I took a little snippet of him that showed him best and put it on Instagram and Facebook and asked friends and clientele to share it around," he said.

The video was shared more than 8,000 times in about 24 hours, Tergesen said.

About six people identified a suspect and contacted Tergesen, who took an unusual step before passing on the information to police.

He sent the suspect a friend request on Facebook.

"He saw the friend request from me, which must have been a bit startling," Tergesen said. "I only wish I could have seen his face. I guess he realized, you know, he was done for at that point, and he better start backpedalling quickly."

The young man messaged Tergesen saying he was turning himself in to police.

Tergesen's has been in business for 117 years. (Supplied) "My response to him was that he was doing the right thing," Tergesen said.

"I'm sure that he had already heard from enough of his friends, and probably even seen the video online, because it had spread around so much. I think he pretty much knew that there was no hope for him."

The thief broke a window, smashed a display case, and stole about half a dozen watches from the 117-year-old business, Tergesen said.

"I made it clear to him that I had a complete inventory of what was missing and that he better bring it all back."