Austin Boutain, 24, was taken into custody Tuesday after a librarian recognized him in a Salt Lake City Public Library and called security, University of Utah Police Chief Dale Brophy told reporters.
"He basically just turned around and surrendered," Salt Lake City Police Chief Mike Brown added. Boutain was taken for questioning by university police detectives, Brophy said.
Boutain's wife, Kathleen, also is in custody, police said.
In addition, police from Golden, Colorado, were flying to Salt Lake on Tuesday to question the couple about the death of a man in the Denver suburb. The victim was identified as Mitchell Bradford Ingle, 63, according to Golden spokeswoman Karlyn Tilley. Ingle died within the last three to five days in a recreational vehicle, Brophy said.
Golden Police Department Capt. Joe Harvey stressed that the Boutains are persons of interest, and not suspects, in the Colorado death. Details of the death were "cloudy," he said, but there was a nexus between the Utah and Colorado cases and police would like to interview the couple.
"We just know they were here," he said, speaking in front of the RV where the body was found.
Kathleen Boutain, 23, was booked into the Salt Lake City jail until Golden authorities can question her, Brophy said. Inmate records indicate she was charged Monday with theft by receiving stolen property, possession or use of a drug paraphernalia and possession or use of a controlled substance.
Brophy said Austin Boutain was being interviewed Tuesday afternoon and would be booked later.
Before he was captured, Salt Lake City police had asked people Tuesday morning to stay away of the Emigration Canyon area, just a few miles east of the university, as the search for Austin Boutain continued.
Around 11 a.m., Salt Lake City police tweeted that the "mountain search for Austin Boutain has been completed" and that the suspect was "still outstanding."
Just before noon, the department tweeted that the suspect was in custody.
A criminal background check did not yield immediate results for Austin Boutain, though police distributed a mugshot indicating he had been arrested in Marion County, Alabama, in the past. Austin Boutain has connections to Minnesota, Wisconsin, Mississippi, Utah and Alabama, said Harvey, who did not elaborate.
Austin Boutain is a suspect in the fatal shooting of ChenWei Guo, a Beijing native the university described as "extraordinarily outgoing, creative, smart and extremely engaged."
According to police, Kathleen Boutain arrived on the University of Utah campus Monday night claiming her husband had assaulted her as they camped in Red Butte Canyon, also in the foothills east of campus. She also told police her husband was possibly armed, a police statement says.
Campus police later received calls reporting shots fired. Brophy said police believe Austin Boutain killed the driver of a car and fled the scene. Police are still searching for a green pickup truck with Colorado tags, the chief said Tuesday afternoon.
University of Utah students were told to shelter in place until 3 a.m. Classes were canceled Tuesday.
After police had determined there was no longer a threat to campus early Tuesday, officers established a perimeter through the night before resuming searching Red Butte Canyon at sunrise.
The Colorado case
Utah authorities contacted Golden, Colorado, police and asked them to conduct a welfare check on an RV, Capt. Harvey told reporters. Officers knocked on the door, but there was no answer. Finding the door unlocked, they entered and found a 63-year-old man dead in the bathroom, Harvey said.
"There were clear signs that this person did not die of natural causes," he said, declining to cite a cause of death before the coroner's office finished its report.
The victim, who was living in the RV and has family in the area, had a green pickup truck with Colorado tags that "may be at large in Utah," Harvey said. The victim did not report his truck missing, he said.
There was "some type of friendly relationship" between the victim and the Boutains, the captain said, but the extent of that relationship was unclear Tuesday.
Investigators with Golden police and the Jefferson County District Attorney's Office were flying to Utah on Tuesday, he said.
The slain student
ChenWei Guo, 23, came to the United States in 2012 and was studying computer science and entrepreneurship at the University of Utah, according to his school profile
. He also was a peer adviser in the International Student and Scholar Services Office.
He hoped to one day own a consulting firm and in his spare time enjoyed skydiving, skiing, horseback riding, dancing, modern fashion and French bulldogs, the profile says.
"We have been in contact with ChenWei's family in China and they are understandably devastated by the loss of their son. We are working to bring them to Utah as soon as possible and will offer them all the assistance we can," school president David Pershing wrote in a letter to students and faculty.