DELPHI, Ind. (WLS) --Â An arrest has been made in the investigation into the unsolved murders of two teenage girls in Delphi, Indiana, sources tell ABC affiliateÂ
The killings of teens Abby Williams, 13, and Libby German, 14, in February 2017 have drawn international attention.
Indiana State Police said they will provide an update on the case Monday morning.
Kelsi German, Libby's sister, tweeted about the upcoming press conference: "Today is the day."
The girls' bodies were found on the property of then-77-year-old Ronald Logan, who is dead. New details reported by ABC affiliate  indicate Logan asked a relative to lie about his whereabouts on the day of the murders.
Last month, the hosts of the true crime podcast "The Murder Sheet" took photographs of investigators scouring the Wabash River, near Peru, Indiana -- about 40 miles from where Abby and Libby were found dead five years ago.
"What we're hearing from sources indicates that this is connected," said Aine Cain, co-host of The Murder Sheet.
Despite thousands of tips since their murder in 2017, their killer is still at large. Libby captured a grainy Snapchat that authorities believe shows their killer, along with a chilling recording thought to be his voice.
"Guys, down the hill," the man says on the recording.
Indiana State Police would only confirm they have a dive team in the area. But the podcasters said it's located just a few miles from the family home of 28-year-old Kegan Kline, who was arrested two years ago and charged with child pornography and child exploitation in a separate case to which he's pleaded not guilty.
According to authorities, Kline admitted to using a phony social media account with the handle "anthony_shots" to communicate with minors.
"He created a completely false persona for himself," said Kevin Greenlee, co-host of The Murder Sheet. "And we know that the Anthony Shots account was actually in communication with Liberty German, who was one of the victims in this case."
Kline has denied any involvement in the murders.
Just days before the podcast hosts say that river search began, a court document obtained by ABC News shows that Kline was temporarily moved from the custody of his local authorities to the hands of Indiana State Police, the lead investigators in the murders of Abby and Libby.
The podcast hosts say it's unclear what officers are looking for in that river.
"A lot of technology comes up in this case of devices that are being used to store child sexual abuse materials or communications with underage girls," Cain said. "And then, of course, weaponry that could have been used in the Delphi murders and any other evidence that could tie a killer to the scene or of the crime, essentially."
Investigators would not say what exactly they are looking for in that riverbed nor how it could possibly be connected to the Delphi murders case.
ABC News' Alex Perez contributed to this report.
