Multiple sources indicate that a man named Richard Allen was booked into the Carroll County Jail Friday in connection with the Delphi murder investigation.

Law enforcement sources told FOX59 that a major development was in the works in the 2017 murders of Libby German and Abby Williams, with a news conference scheduled for Monday with additional details.

The teens disappeared on the Monon High Bridge on Feb. 13, 2017. They were reported missing, and their bodies were found around noon on Feb. 14, 2017.

Police released two different sketches of potential suspects. Key evidence included audio and photos from Libby German’s phone, with police releasing an audio clip of a man saying, “Down the hill.”

An FBI agent believed there was probable cause to search the property of Ron Logan, who owned the land on which the girls’ bodies were found.

The search warrant revealed additional details about the investigation, including that the recording in which the “down the hill” audio originally lasted 43 seconds

Additionally, investigators found a large amount of blood at the scene, leading them to believe the perpetrator would’ve gotten blood on their hands or clothing.

In recent months, Indiana State troopers have been searching the Wabash River in Peru potentially looking for evidence tied to the case.