ABC News February 16, 2017

Police search for a man photographed in area where slain Indiana teens had been hiking

WATCH: FBI joins investigation into the death of missing teen girls in Indiana

Authorities in Indiana have released an image of a man they say was photographed on a nature trail around the same time as two Carroll County teenagers were hiking before they disappeared and were later found dead.

"We are asking help from the public to help identify him so he can be contacted regarding what he might have seen," police said in a statement Wednesday. "Also, if you were parked at High Bridge Trail Head on February 13, 2017 between 1:00 p.m. and 5:00 p.m. we would like to talk to you."

Teen girls found dead on hike in Indiana investigated as double homicide

On Wednesday, authorities identified the bodies of Liberty Rose Lynn German, 14, and Abigail J. Williams, 13, both of Delphi. Police said the FBI was assisting in the investigation.

Police said the girls had been dropped off for a hike around 1 p.m. Monday. About 2.5 hours later, the girls were nowhere in sight when their families came looking for them, police said.

On Tuesday, German and Williams were found around 12:15 p.m., roughly a quarter-mile from an abandoned railroad bridge, near Delphi. Police said they were investigating the deaths as homicides.

They did not release a cause of death and did not detail any wounds or injuries the girls may have sustained.

Carroll County Sheriff Tobe Leazenby said technology, specifically the girls' social-media accounts and cell phone records, was important to the investigation.

"At this stage, we don't know whether or not they're, maybe someone, is holding back for fear of something or any other reasons. We honestly don't know but that picture [of the man] is important for us to be able to move forward in this investigation," Leazenby said. "Maybe there's a message that was conveyed, maybe at some point, whether it be social media or any other technology, that we haven't uncovered yet."

Leavenby would not say whether the victims' cell phones had been recovered. Police would not disclose the source of the photograph of the man whom they would like to interview.

"It's a very tight-knit, close community," Leavenby told ABC News today. "It's not like anything we've had in our past. ... This one has a different feel to it. ... These were wonderful girls. ... This was their innocence taken away from them at a very young age."

ABC News' Alex Perez and Andy Fies contributed to this report.