Maryland Natural Resources Police said it's been five months and they still don't know whose remains they found in Cunningham Falls State Park.
Police were only able to put together a sketch after finding a skull and bones in May and they're hoping someone recognizes him.
"These are Hail Mary passes and we're hoping to connect again," said Candy Thompson, a police spokesperson. "We obviously checked with police departments in the region, missing persons reports, social services agencies to see if someone had been reported missing."
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A hunter found the remains just inside Cunningham Falls State Park.
"About 40 yards off the road is where the first bones were found and the rest of them weren't very far away," Thomson said.
She said investigators spent weeks trying to connect the dots back to the 'John Doe' by looking for clues in the area. They couldn't find anything, giving them little leads and no answers.
"We even brought out our academy class, from the police academy, to help us search shoulder to shoulder in the woods looking for remains," Thomson said.
A forensic team took what they could to piece together a sketch of a black male between 16 and 19 years old. The body was in the park for at least a year.
Thomson said a medical examiner couldn't determine how or where the teen died.
"We've now exhausted all of our look at all of those things," she said.
With nowhere to go, police are relying on the sketch hoping someone recognizes the teen.
"Our hope is that during this holiday season as people reach out to family members that they may not have seen for awhile, that someone will realize that someone who looks like this, who's about this age and size, that that person is missing," Thomson said.
Thomson said the department put out a sketch of a man before and a family recognized him and reached out. She's hoping it happens again.