A photo of a St. Paul police officer giving a thumbs-up next to a man who appears to be unconscious – an image that quickly spread on social media – is getting some explanation.

Dave Titus, president of the St. Paul Police Federation, describes the scene to the Pioneer Press as "a lighthearted moment amongst friends."

Titus said officers were finishing a call on an unidentified day that was much warmer than it is now – hence the short sleeves – and spotted the man in the car. They went to investigate further and the man turned out to be the officers' friend.

The newspaper says one officer took a photo of the other officer posing with the sleeping man before he was awakened.

Titus said the man was not under the influence nor had he been pulled over, and officers made sure he was breathing before snapping the pic.

A source within the St. Paul Police Department told KSTP that the officers' friend was sleeping in his car during a break from work.

The unidentified man posted the photo on Facebook, according to Titus, and from there it traveled to several other social media sites, the Pioneer Press reports.

St. Paul Police spokesman Paul Paulos says Chief Tom Smith is aware of the photo and the matter is under investigation.

"You have to remember, whether you're on duty or not, that you represent the St. Paul Police Department," Paulos told City Pages. "This could fall under 'conduct unbecoming.' There are a set of rules and the chief will have to go off that once the findings are made."