Scott Kimball – a former FBI informant serving prison time for four murders – is facing new charges that he attempted to arrange a killing from behind bars and escape from the Sterling Correctional Facility, 9Wants to Know has learned.

Kimball, 51, has not yet been advised of the new charges he could face, Brittny Lewton, the district attorney for seven northeast Colorado counties, told 9NEWS on Thursday.

Lewton confirmed that the arrest warrant was filed Tuesday in Sterling.

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A judge sealed the affidavit – which would lay out the case against Kimball – but the warrant itself, obtained by 9Wants to Know, shows that it was obtained by the FBI and that Kimball faces one count of solicitation of first-degree murder and one count of attempted escape.

The warrant calls for Kimball to be held without bail – a formality, since he is behind bars and won’t be eligible for parole until 2054, when he would be 88 years old.

It is not clear when Kimball, who is serving 70 years in the killings of three young women and his uncle while acting as an FBI informant in 2003 and 2004 – could appear in court to be advised of the new allegations.

Other details of the new case were murky Thursday.

Kimball, a lifelong con-man, was behind bars in Alaska in a check fraud case when he provided information to the FBI about a plot to kill a federal judge, beginning life as a federal informant. He also claimed at various times to have information about the murder of an assistant U.S. attorney in Seattle.

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Investigators later came to doubt the truthfulness of his claims in either of those cases.

He was moved to Denver in 2002, and he later convinced FBI agents that his cellmate, a man named Steven Ennis, wanted him to kill a witness in a drug case.

On Dec. 18, 2002, a federal magistrate allowed for Kimball to be released from custody “to actively cooperate with the FBI on the Steven Ennis matter,” according to previously released court documents.

But instead of cooperating, Kimball murdered at least four people – and has been considered a potential suspect in other killings.

In the eight months after his release, Kimball killed LeAnn Emry, 24, Jennifer Marcum, 25, and Kaysi McLeod, 19.

Then, in mid-2004, he shot and killed his uncle, Terry Kimball, 60.

It wasn’t until 2006 that the fathers of Marcum and McLeod convinced the FBI to begin looking at Kimball as a suspect at what was then the disappearances of the young women. By then he was also a suspect in an elaborate check-fraud scheme in Boulder County.

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In 2009, Kimball struck a deal with prosecutors. He led investigators to the remains of Emry in a Utah canyon and Terry Kimball in a forested area near Vail. A hunter found McLeod’s skull in the mountains of north-central Colorado in 2007.

Kimball never revealed the location of Marcum’s body, and it has never been found.

Kimball pleaded guilty in the four killings and was sentenced to 70 years in prison. That’s on top of 48 years he is serving in a fraud case.

At the same time, Kimball has been looked at as a potential suspect in several unsolved disappearances and murders but has never been charged in any of them.

Contact 9NEWS reporter Kevin Vaughan with tips about this or any story: or 303-871-1862.