Libby German, 13, and Abby Williams, 14, were abducted and murdered while hiking a trail in Delphi, Indiana
liberty german and abigail williams
Libby German and Abby Williams
| Credit: Courtesy Mike and Becky Patty

Authorities in Indiana investigating the unsolved murders of two best friends are looking into a 42-year-old man accused of kidnapping and sexually assaulting a 9-year-old.

James Brian Chadwell II has been charged with attempted murder, child molesting, attempted child molesting, kidnapping, criminal confinement, battery resulting in serious bodily injury and strangulation. He is accused of luring a 9-year-old into his Lafayette house on April 19, according to the Journal Courier, WTHR and Fox59.

Chadwell allegedly brought the child to his basement, where he beat her and sexually assaulted her until police knocked on his front door. The girl was discovered locked in Chadwell's basement during a search of his home. She told investigators she believed Chadwell was going to kill her.

The girl was reported missing about 30 minutes after she was last seen.

Now, according to Carroll County Sheriff Tobe Leazenby, investigators are looking into Chadwell for the 2017 murders of Liberty "Libby" German and her best friend, Abigail "Abby" Williams, the Courier, WGN and WSBT report.

On Feb. 13, 2017, 13-year-old Libby and 14-year-old Abby were abducted and murdered while hiking a trail in Delphi. Their bodies were found the following day alongside a creek about a mile from where they were last seen.

Little is known about how the girls died. However, before they died, Libby captured a video and audio clip on her phone, in which the suspect can apparently be heard saying, "Guys, down the hill."

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James Brian Chadwell II
Credit: Tippecanoe County Jail

Chadwell is not the first person authorities have investigated since Libby and Abby's deaths. However, no arrests have ever been made in the case.

"We've waited so long for answers," Libby's older sister, Kelsi German, previously told PEOPLE, "so it would be nice to have closure and the girls can have their day and we can be done."

This month, the Indiana State Police announced that thanks to an anonymous donation of $100,000, the reward for information leading to a conviction in the case has increased to $325,000.

Anyone with information on the case is encouraged to contact law enforcement by emailing or calling 844-459-5786.