A photo hidden under a 2-year-old pit bull's collar has left a local animal shelter baffled.

The dog was brought into Greenville County Animal Care on Jan. 13 in Greenville, S.C. But to the surprise of the shelter staff, there was a worn, black-and-white photo tucked into the animal's collar.

"It's a really small photo, it's black and white, of a man leaning against a gate post or a railing," Susan Bufano, the shelter's media relations coordinator, told GoodMorningAmerica.com. "Who knows what the story is with this."

The shelter staff named the pit bull Soldier. But seeing that he has no identification tag or any other means to locate his possible owner, the significance of the photo placed in his collar isn't known.

"It is really interesting," said Bufano. "I was asking the staff if they have ever seen this before, but no. A dog came in once with a cape on, a very shy dog, but we've never had anything here like this." She also claims that the collar Soldier was wearing in a little different from the types normally seen by the shelter, adding to the mystery of the stray animal and his origins.

The shelter has posted Soldier's story on its Facebook page. However, no leads have been discovered so far.