(CNN) - The torrent of tips shows how badly strangers want to find Libby German's and Abby Williams' killer.
Just 24 hours after police released a new sketch of a man they say killed the Indiana girls, more than 1,000 new leads have poured in, Indiana State Police Sgt. Kim Riley said Tuesday.
That's an average of almost one new tip every minute, around the clock. By contrast, investigators have typically received about 12 tips a day since the girls were killed in February 2017.
On Monday, police released the new sketch and additional video from a victim's cell phone in hopes the case will finally be solved.
Libby, 14, and Abby, 13, were reported missing on February 13, 2017, after they went hiking at Delphi Historic Trails in Indiana.
When they didn't show up at a designated meetup time, an extensive search ensued. Their bodies were found the next day in a wooded area near the trails, about a half mile upstream from where they had been dropped off.
Now, Indiana State Police Superintendent Doug Carter said he believes the killer lives in, works in or frequents the Delphi area.
"We believe you are hiding in plain sight," Carter said at a news conference Monday. "For more than two years, you never thought we would shift gears to another investigative strategy. But we have."
The police chief continued speaking openly to the killer, who he said "may be in this room."
"What will those closest to you think of when they find out you brutally murdered two little girls -- two children? Only a coward would do such a thing," he said.
"We are confident that you have told someone what you have done. Or, at the very least, they know because of how different you are since the murders."
Authorities previously released a grainy photo of a suspect, which shows a man wearing blue jeans, a blue coat and a hoodie.
At that time, officials also released audio of a male voice saying the words "down the hill," hoping someone might identify the suspect's voice. The voice recording was taken from a video found on Libby's cell phone, police said.
Indiana State Police spokesman Capt. Dave Bursten has praised Libby as a hero for having the presence of mind to turn on her video camera.
But the tragedy has been grueling for the girls' families.
Kelsi German, Libby's sister, remembered Libby as a fun, outgoing person who loved playing sports and was interested in photography. She said she last saw Libby and Abby when she dropped them off on the hiking trails two years ago.
"They got out of my car. I made sure they both had sweatshirts and told them goodbye. I told Libby I loved her," German told HLN in February. "They walked out, and that was the last time I saw them."
HLN's Barbara MacDonald and CNN's Eric Levenson and Carma Hassan contributed to this report.
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