KUSA – The 24-year-old man accused of gunning down a University of Utah student and who is also being considered a “person for interest” in a homicide that occurred in Golden admitted to investigators that he stole three firearms from a residence in Colorado.

That’s according to a probable cause statement obtained by 9NEWS from University of Utah campus police.

Austin Boutain is being held by the Salt Lake County Sheriff’s Office on charges of aggravated murder, aggravated robbery causing serious bodily injury, attempted homicide and various weapons charges, according to the arrest report.

He was taken into custody Tuesday afternoon after he was spotted by a librarian inside the Salt Lake City downtown public library.  It came on the heels of a manhunt that lasted for hours in the mountains surrounding the University of Utah following the botched carjacking and fatal shooting of ChenWei Guo, a student from China, late Monday night.

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According to the probable cause statement, Boutain admitted to shooting and killing Guo, and conceded that he planned on stealing his vehicle.

Details about where the weapons from Colorado were stolen were not written in the police report. It’s unclear if these three guns were related to the investigation surrounding the death of 63-year-old Mitchell Bradford Ingle, whose body was found in an RV in Golden.

Golden Police conducted a welfare check on Ingle early Tuesday morning after receiving a request to do so from Salt Lake City Police.

Golden Police Captain Joe Harvey was cautious not to name Boutain and his wife as suspects in the death investigation of Colorado. Instead, during a news conference on Tuesday, he referred to them as “persons of interest” and said that detectives were flying to Salt Lake City to interview them.

Harvey said knives and guns could be missing from Ingle’s RV.

Harvey also said that the green Toyota truck the Boutains were believed to be badociated with belonged to Ingle.

Boutain’s wife, Kathleen, is also in custody on unrelated drug charges. According to a probable cause statement from the Salt Lake County Sheriff’s Office, she said she knew she was traveling in a stolen vehicle with stolen guns.

Just before her husband allegedly shot Guo, University of Utah Police say Kathleen Boutain reported a domestic violence incident.

In the probable cause statement for Boutain, police said they believe he fired two rounds at a woman, who ran away. The woman’s name is redacted, and it’s unclear if this part of the report is referring to Kathleen Boutain.

Later, the probable cause statement says Boutain “badaulted his wife with a firearm, causing injury to her.”

9NEWS has contacted the University of Utah Police Department and is hoping to clarify details about who else Boutain is accused of firing a weapon at. We are also working to determine if the guns were taken from Ingle’s home.

According to the probable cause statement, Boutain told investigators he traded one of those guns – a .38 caliber Smith and Wesson, for an ounce of marijuana.

He told police another weapon, which he said he used in the shooting, was hidden in the crevice of a brick wall near the homeless shelter. When he went to retrieve the weapon, it was missing, according to the probable cause statement.

Another weapon used in the homicide, according to the probable cause statement, was found at the Boutain’s camp in a nearby canyon. 

Guo’s death prompted the University of Utah to cancel clbad on Tuesday. He was remembered by the university as “extraordinarily outgoing, creative, smart & extremely engaged.” 

We’re absolutely heart-stricken by the loss of student ChenWei Guo. He was “extraordinarily outgoing, creative, smart & extremely engaged.” pic.twitter.com/cOqkRzu91t

— University of Utah (@UUtah) October 31, 2017

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