A sketch police believe may depict the face of the killer behind the 2017 slayings of two girls in Indiana and that was released to the public on Monday was actually drawn two years ago -- just days after the victim's bodies were discovered.

Indiana State Police said at a news conference the sketch shows the unidentified man suspected of murdering Libby German, 14, and Abby Williams, 13. Officials said the man is likely between the ages of 18 and 40, but may appear younger. He's also believed to have lived, worked or regularly visited Delphi, which is located about 60 miles northwest of Indianapolis.

The sketch artist with ISP who drew the face, Master Trooper Taylor Bryant, told the Indianapolis Star the picture presented as being new Monday had in fact been drawn Feb. 17, 2017, three days after the bodies of the two girls were discovered.

DELPHI MURDER INVESTIGATION FEATURES NEW SKETCH, BACKGROUND ON 'HEARTLESS' KILLER OF 2 INDIANA GIRLS

In vague terms, Bryant told the Star the image was based on the description of a man by a witness who reported seeing something they felt needed to be reported. The sketch is a "ballpark estimation of what the person looks like."

Bryant, who did not draw an earlier, widely-disseminated sketch released by police that showed a much-older looking person of interest, told the Star he creates his drawings based off how a witness describes a suspect using a "facial identification reference sheet," which allows people to describe a suspect based on various categories such as a person's head shape, style of eyebrows or type of nose.

"The witness is the main focus," he told the paper. "So there’s no input from law enforcement at all in the generating of a sketch, other than my presence as the artist."

Asked why a sketch created in 2017 was only now being released -- as the centerpiece of a press conference -- a state police spokesperson told Fox News on Tuesday the agency is not commenting on investigative techniques.

But on Monday, officials said the new image came about after some bit of new information that had been "continuously reviewed and examined." Authorities said the image "more accurately" depicted the face of the suspect from video recorded on German's cell phone while she and Abigail were on the High Bridge.

The new brief video released by authorities shows a man walking on the High Bridge in the hopes that someone could identify the individual based on the mannerisms as he walks. In the course of the investigation into the murders, authorities had previously released a pixelated image of the same man from that video walking on the bridge around the time of the girl's disappearance.

Besides the video and new image, ISP Superintendent Doug Carter revealed that investigators were looking for the owner of a vehicle abandoned on the east side of County Road 300 North next to the Hoosier Heartland Highway between 12 p.m. and 5 p.m on Feb. 14, 2017, the day the girl's bodies were discovered. The vehicle was parked at the old CPS/DCS/Welfare building, according to Carter.

2017 DELPHI MURDERS OF 2 TEENAGE GIRLS MOVING IN 'NEW DIRECTION,' INDIANA STATE POLICE SAY

The teens were reported missing on Feb. 13, 2017, after they were dropped off at the Delphi Historic Trails in the early afternoon to go for a walk. Their bodies were discovered the next day by a volunteer, about a half-mile off the trail. Despite autopsies being conducted, no cause of death has ever been revealed for either of the girls. Police have tens of thousands of tips in the investigation into Williams' and German’s deaths but have not yet made any arrests.

"We believe you are hiding in plain sight," an emotional Carter said, addressing the killer directly during the news conference. "For more than two years you never thought we would shift to a different investigative strategy, but we have."

A retired homicide investigator with the Indianapolis Metropolitan Police Department told FOX59 "sketches in any crime can be tricky" because they aren't exact photographs, but can still prove valuable for generating tips.

“Sketches are worthwhile, but you never want to take it at 100 percent value and think they have to look exactly like the sketch, because they won’t,” retired homicide captain Robert Snow told the television station.

"I have never seen sketches that look exactly like a person, again it’s not like a photo, but it can give you some suspects sometimes," he added.

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Snow, who told FOX59 he didn't have any inside information about the investigation or why it took two years for the video of the man to be released, praised the actions of state police to keep the case in the spotlight.

“The nice thing is state police haven’t given up," he told FOX59. "They are still working full force even after two years."

Authorities are encouraging anyone with information to contact the tip line at 844-459-5786 or email them to Abbyandlibbytip@cacoshrf.com.