Indiana authorities have arrested a man in the unsolved slayings of two teenage girls who were killed while hiking five years ago near their small community in northern Indiana hometown, police said Monday.Indiana State Police Superintendent Doug Carter said during a news conference that Richard Matthew Allen, 50, was arrested Friday on two murder counts in the February 2017 killings of Liberty German, 14, and Abigail Williams, 13, in a case that has haunted the Indiana city of about 3,000 people.The bodies of Libby and Abby were found in a rugged area near a hiking trail on Feb. 14, 2017, one day after they vanished while hiking during a day off school.A relative of one of the teens dropped them off at the hiking trail near the Monon High Bridge just outside their hometown of Delphi, about 60 miles northwest of Indianapolis. They were reported missing on the evening of Feb. 13, 2017, after failing to appear at a predetermined meeting place.Their deaths were ruled a double-homicide, but more than five years after the killings police have not disclosed how the girls died or described what evidence they had in the case.Within days of the killings, investigators released two grainy photos of a suspect walking on the abandoned railroad bridge the girls had visited, and an audio recording of a man believed to be the suspect saying "down the hill."Authorities have since released two sketches of the suspected killer, including one in April 2019 based on video from Libby's cellphone that's believed to be more accurate than a sketch released in July 2017.Police also released video in April 2019 which shows the man suspected of killing the teens walking on the abandoned railroad bridge the girls had visited.The brief video, photos and audio of the suspect came from Libby's cellphone. Authorities have hailed her as a hero for recording potentially crucial evidence before she was killed.In December 2021, state police announced they were seeking information from people who had contact with someone who used a fictitious online profile to communicate with young girls.State Police said at that time that investigators probing their deaths had uncovered a fictitious online profile named "anthony_shots" that was used from 2016 to 2017 on Snapchat, Instagram and other social media platforms.Additional reporting by The Associated Press.