Documents show that UCLA gunman Mainak Sarkar married Ashley Hasti in 2011. (File Photo)
The path to the campus shooting death of a UCLA professor began nearly 2,000 miles away in Minnesota.
There, a former student with a grudge, Mainak Sarkar, killed a woman, police said. That woman was his estranged wife, according to relatives, neighbours and public records.
Sarkar then made the long drive to Los Angeles where he found his former mentor, engineering professor William Klug, and shot him before turning the gun on himself, authorities said Thursday.
Both victims were on a "kill list" police had found at Sarkar's Minnesota apartment. A third person on the list, another UCLA professor, was spared because he was not on campus Wednesday when Sarkar arrived with two semi-automatic pistols, police said.
Authorities did not publicly identify the unharmed professor or the woman. A law enforcement official with knowledge of the investigation told The Associated Press that the woman on the list was Ashley Hasti, who documents show married the gunman in 2011.
The investigation unfolded rapidly based on a note Sarkar left in the office where he killed Klug. It asked anyone who read it to check on Sarkar's cat in St. Paul, Minnesota.
At Sarkar's apartment, authorities found his list of three planned targets. They checked the residence of the woman in the nearby town of Brooklyn Park and found her body.
The law enforcement official said Hasti was the name of the woman on Sarkar's list. Beck said the woman named on the list was the victim; and a neighbor told AP that Hasti lived in the home with her father.
The official who said Hasti's name was on the list was not authorized to publicly discuss the case and spoke on condition of anonymity.
Gordy Aune Jr, who lives three doors away and is the neighbourhood watch commander, said Hasti and her father kept to themselves.
Records in Hennepin County, Minnesota, show Hasti married Sarkar in 2011, though more recently they had different residences.
Hasti's grandmother, Jean Johnson, said the two only remained together for about a year, but didn't get a divorce because Hasti couldn't afford one.
"They just didn't get along," Johnson told the Minneapolis Star-Tribune. "The only enemy she had was him, I guess. I never thought he would do something like that."
She said she hadn't mentioned any recent animosity with Sarkar.
Sarkar had disparaged Klug online and the professor knew of his contempt, but police have not uncovered any death threats, Beck said. The writings contained "some harsh language, but certainly nothing that would be considered homicidal," he said.
A blog post written in March by someone identifying himself as Sarkar asserted that Klug "cleverly stole all my code and gave it (to) another student" and "made me really sick."
Beck said the investigation had shown Sarkar's claims of stolen code are "a making of his own imagination."
Sarkar, 38, and Klug, 39, were once close. In his 2013 dissertation about using engineering to understand the human heart, the student thanked the professor "for all his help and support. Thank you for being my mentor."
It's unclear what he had been doing since.