Since two Indiana girls were slain while hiking five months ago, as many as a dozen police detectives have worked daily to track down their killer.

First, authorities released a blurry photo of the suspect. Next came a brief but eerie recording of a man’s voice saying “down the hill.”

Both were discovered on victim Liberty German’s cellphone.

Then on Monday, investigators released a new FBI composite sketch depicting a white male with reddish brown hair and a goatee that the Indiana State Police said gives people “a better view of the person.

All along the way, authorities have relied on the public for help.

Now, they’re pulling back — and asking wannabe detectives on social media to stop “armchair sleuthing.”

People on Facebook have been posting the FBI sketch alongside photos of random men or mug shots they combed for on the Internet, state police chief public information officer Capt. Dave Bursten told the Indianapolis Star. They may slightly resemble the suspect, Bursten said, but the “armchair sleuthing” is “of no value” and will only “take up investigative time.”

“A person that does that may open themselves up to some civil liability,” Bursten said. “They will have to suffer the consequences of their own stupidity.”

More than 1,300 tips have been called into the phone hotline or emailed to authorities since the sketch was released Monday, but Sgt. Kim Riley with the state police told Fox 59 that social media is not where investigators are scrolling for help.

“You’re putting people’s lives, families and children in danger by putting pictures that may have nothing to do with this case,” Riley told the TV station.

“You’re just being Joe detective out there trying to be the one to break the case,” he continued, “and that’s not the way to do it.”

In fact, Riley said, online speculation might damage the case.

Since 14-year-old Liberty German and 13-year-old Abigail Williams were killed in February, detectives have looked at 1,000 persons of interest, Fox 59 reported. This week, the number of investigators on the case has jumped from around 10 to nearly 30, according to the TV station.

The girls were reported missing by their families Feb. 13, after they went for a hike on the Delphi Historic Trails in Carroll County, Ind., about halfway between Indianapolis and Chicago. Their bodies were discovered by a search party the next day in a wooded area.

Liberty German, left, and Abigail Williams were killed in Delphi, Ind., in February while hiking. (J. Kyle Keener/Pharos-Tribune via AP)

“Someone knows who this individual is,” Indiana State Police Superintendent Douglas Carter said at a news conference on Feb. 22. “Is it a family member? Is it a neighbor? Is it an acquaintance? Is it an associate? Or maybe that one guy, who lives over at that one place that just [is] kind of not right.”

The composite released Monday drew upon “recent information” from a witness who saw the suspect around the time of the killings, Carroll County Sheriff Tobe Leazenby told the Lafayette Journal & Courier.

“It relates to a dialogue between a witness and a sketch artist,” Leazenby told the newspaper. “That’s based upon an actual, real situation.”

Authorities believe the man weighs 180 to 220 pounds and is between 5-foot-6 and 5-foot-10.

“It shows a little more facial features, it gives you a little more information on what we’re looking at, who the suspect might be,” Riley told Fox 59, “and that’s why we feel that it’s very important that this picture is out there at this time.”

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