The killer of two teenage girls, who were slain in 2017 while they were hiking in their small Indiana city, has close connections to the community, police said Monday.

"Directly to the killer — who may be in this room — we believe you are hiding in plain sight," Indiana State Police Superintendent Doug Carter said during a news conference. "We likely have interviewed you or someone close to you."

"For more than two years, you never thought we would shift gears, but we have," he said. "We know this is about power to you, and you want to know what we know. And one day you will."

Liberty German, 14, and Abigail Williams, 13, vanished while hiking in their hometown of Delphi, about 60 miles northwest of Indianapolis, in February 2017. Their bodies were found in the woods the day after they disappeared.

Carter said Monday that their murderer likely lived in, worked in or often visited Delphi, a city of about 3,000 people.

He said investigators were looking for tips on a vehicle parked next to an abandoned building near Hoosier Heartland Highway the day the girls went missing.

Police also released a new sketch of the suspect, which bears little resemblance to the one they released in July 2017.

"We have a witness. You made mistakes. We are coming for you and there's no place for a heartless coward like you to hide that gets his thrill from killing little girls," Carter said in a statement accompanying the new information.

Investigators, at first, released two grainy photos of a person walking on an old railroad bridge the girls had visited on their hiking trip, along with audio of a male saying, "Down the hill." The evidence had come from Liberty's cellphone.

Police on Monday released more evidence obtained from Liberty's cellphone — a longer audio clip, in which the same male seems to be saying "guys" and video of the person walking on the bridge.

Carter encouraged Delphi residents to "watch the person's mannerisms as they walk" so they could determine whether it might be someone they know.

He vowed that he would not give up on the investigation. "We are just beginning. We are just now beginning," he said. "We will not stop."