A long-haul truck driver who was arrested last year in connection to at least 11 cold-case rapes in Utah and Wyoming is now being investigated in connection to at least three unsolved murders.

As Fox 13 Salt Lake City first reported this week, multiple sources at several law enforcement agencies have revealed that Mark Douglas Burns, 69, has confessed to being a serial killer and claiming the lives of at least three people.

As of Wednesday morning, Burns has not been charged with any additional criminal offenses, and the Davis County District Attorney’s Office has not commented on the new allegations.

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Accused Utah serial rapist Mark Douglas Burns, 69, allegedly has admitted to killing at least three people and sexually assaulting additional women

Burns was arrested in September 2019 (seen in court) following a years-long investigation using familial matching DNA samples in collaboration with a true-crime TV show

Courtesy of Fox 13

Burns, who lived in Ogden, Utah, was arrested in September 2019 following a years-long investigation using familial matching DNA samples in collaboration with a true-crime TV show.

Burns was charged in Utah with 17 felony counts, including aggravated sexual assault, aggravated burglary and kidnapping, stemming from 11 rapes that took place between 1991 and 2001.

In at least one case, Burns allegedly forced a victim’s family members to watch the rape.

During his time in jail, Burns allegedly has admitted to raping more women, and also committing at least three homicides.

Unnamed law enforcement sources have told the station that Burns has been linked to the July 2001 shooting death of Sue Ellen Gundrson Higgins, a 28-year-old married mother-of-one, in her driveway of her family’s home in Evanston, Wyoming.

Modus operandi: In each of the 11 rapes that Burns has been named a suspect, the victims were bound and raped repeatedly in front of family members by an attacker who smelled of alcohol and was armed with a knife or a gun

Higgins’ widowed husband was arrested in Aztec, New Mexico, in 2005 in connection to her slaying, but charges against him were dismissed a year later.

Uinta County prosecutor Mike Greer cited 'irregularities in forensic evidence analysis and other evidence' in the decision to drop the case without prejudice.

DailyMail.com on Wednesday reached out to the Evanston Police Department for a comment and was told that the agency 'can neither confirm nor deny' any information pertaining to the Higgins murder investigation, which remains open and active.

A press release issued in September 2019 by the Clearfield Police Department in Utah described Burns as a 'serial rapist.'

'The sexual assaults were incomprehensible, brutal and methodical attacks on females,' police said. 'In addition, family members were forced to watch the violent and repeated attacks.

According to the statement, the agency investigated multiple rapes in Clearfield between 1994 and 2001, and collected DNA evidence.

In 2003, a DNA warrant was obtained concerning additional sexual assaults that took place in 2001 and 2003, but at that time, those rapes were not linked to the sexual assaults that were reported in the 1990s.

In 2010, with the advancement of DNA technology, four more sexual assaults were linked to the 2001 and 2003 cases in Clearfield when the DNA evidence was entered into the Combine DNA Index System (CODIS).

Eventually, DNA linked a total of 11 cold-case rapes that occurred in Rock Springs, Wyoming, in 1991; Riverdale City, Utah, in 1992; Ogden, Utah, in 1993; Clearfield, Utah in 1994 and 1995; Laramie, Wyoming, in 1996; Layton, Utah, in 1997, and four more cases that were reported in Clearfield in September 1997, May and July 2000, and May 2001.

A police probable cause statement cited by Deseret News said that in the 2000 incident, a woman said she was asleep when a stranger woke her up and threatened to 'cut her throat' if she said a word. He then blindfolded her and proceeded to rape her multiple times before tying her up and leaving.

The 2001 case involved a home invasion during which a woman and her 19-year-old were both raped at gunpoint in front of their male family members.

According to the police, in each of the rapes, the attacker bound the victim and proceeded to rape her repeatedly over an extended period of time.

All the victims reported that their assailant smelled of alcohol, gained access to their homes through sliding glass doors, and was armed with a gun or a knife.

Until his arrest, Burns lived in Ogden, Utah, and worked as a long-haul trucker driver

Police departments in Utah and Wyoming worked with the TNT television show Cold Justice Sex Crimes to link the nine cases together using DNA matches, and later enlisted the help of genetic genealogist Dr Barbara Rae-Venter to study previously collected samples to discover a potential familiar DNA relationship.

Over the course of several months in 2019, detectives followed several leads before ultimately zeroing in on Mark Burns, of Ogden, as the prime suspect.

His DNA was then tested and confirmed to match the DNA warrant profile connecting him to all nine rapes, according to the police.

The Davis County District Attorney’s Office has charged Burns with eight counts of aggravated sexual assault, six counts of aggravated kidnapping, two counts of aggravated burglary and one count of aggravated robbery.

Investigators suspect that there may be additional victims out there, especially in Western United States, given Burns’ occupation as a long-haul truck driver.

'These sexual assaults have caused a tremendous amount of pain and grief with all victims and family members,' the police press release stated. 'Because of the grievous nature of these crimes, detectives believe there are more victims and do not believe Mr Burns suddenly stopped committing such heinous crimes since 2001.'

Burns was convicted of rape in North Carolina in 1974 and served a lengthy prison sentence before moving to Utah, a charging document states.