Transcript for Grandfather of murdered Indiana teen speaks out
But we begin with the hunt for the suspect in that Indiana murder mystery. The family of one of those young girls begging for help revealing new details about the teens. Alex Perez is in Indiana with much more. Good morning, Alex. Reporter: Hey, good morning, robin. Even though it seems the investigation has stalled, the victims' family members say they have not given up and hope by speaking out they might be able to help investigators get the tips they need. This morning, Libby German's grandfather speaking out. Somebody is out there that's done this. They need to be brought to justice. Reporter: And imploring the public to help find his granddaughter's killer. I believe if she were able to speak she would ask people to study the picture. Reporter: Also sharing what led the teenage girls to this hiking trail and railroad bridge on that fateful day. She's kind of a photo buff anyway. That's why the girls were out there taking pictures. That's why they went out there in the first place just to catch the scenery. Reporter: Those photos taken by Libby showing her friend Abby on the railroad bridge and at one point Libby kept her smartphone camera rolling explaining what may have led his granddaughter to hit record. Obviously she had presence of mind, sensed something a little strange there. Reporter: That presence of mind resulting in this image of a man in a blue jacket and this voice. Down the hill. Down the hill. Reporter: Authorities confirming to ABC news that that voice belongs to the man seen in this still image and authorities hope these clues will eventually lead investigators to the suspect responsible for the double homicide. Since their bodies were discovered on Valentine's day, over 11,000 tips have been submitted. A sign to a team of hundreds of officers is spanning 25 police agencies including the FBI. This high-profile case taking a toll on the law enforcement leading the hunt. This is emotional for all of us. Reporter: As friends today remember them and Abby's career aspirations. In police work and law enforcement we shared. Reporter: The reward for any information leading to an arrest is now up to $250,000. Hopefully that will help. Alex, thank you.
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