Police officers rushing to the University of California at Los Angeles after reports of gunshots were worried there might be an active shooter on campus, but instead they discovered a “contained” murder-suicide involving a gunman killing his former professor. They also found a note asking authorities to check on the gunman’s cat nearly 2,000 miles away.

That note began to unravel an unusual, violent plan, with police on Thursday discovering a “kill list” in the shooter’s Minnesota home that included a woman who was found dead outside Minneapolis, said Charlie Beck, chief of the Los Angeles Police Department.

Police believe the gunman – Mainak Sarkar, 38 – traveled to UCLA on Wednesday with a grudge against William Klug, 39, the engineering professor who chaired his mechanical engineering doctoral dissertation committee three years earlier. They also said Sarkar, carrying two semi-automatic pistols and extra ammunition, also intended to kill another, unidentified UCLA professor – the third person on his list – but that professor apparently was off-campus when Sarkar arrived.

“Sarkar was heavily armed,” Beck said during a news conference Thursday, adding that the guns appeared to be legally purchased. “He had multiple magazines of ammunition and multiple loose rounds of ammunition. He was certainly prepared to engage multiple victims with the ordnance he had.”

POLICE FIND INSTRUCTIONAL NOTE

The gunman made his way to Klug’s fourth-floor office in an engineering building and fatally shot Klug – a husband and father of two – before quickly taking his own life, Beck said.

When police arrived at the scene, they found what Beck described as “an instructional note to the finder to check on his cat, which we did.” That note led authorities to Sarkar’s home in St. Paul, Minnesota, where they found more ammunition and his “kill list,” Beck said.

Because this list included the name of a woman in Brooklyn Park, Minnesota, the LAPD asked police in that city to visit her home. Officers arrived just after midnight and found her dead with a gunshot wound, which police said occurred before the UCLA shooting.

Police have not released the woman’s name, and Beck said he could not immediately elaborate on her possible relationship with Sarkar.

“We’re trying to coordinate our efforts between Minnesota and California with this investigation, which is very complex,” Mark Bruley, deputy chief of the Brooklyn Park police, said during a news conference.

‘MENTAL DERANGEMENT’ LIKELY

Beck said police are working on finding a possible motivation for the shooting, but he said it appeared to be a case of “mental derangement.” Police provided little information about Sarkar, and details about his life at UCLA and in Minnesota were elusive Thursday; colleagues declined to comment about him.

“Everybody tries to look for a good reason for this,” Beck said in an interview Thursday morning on KTLA. “There is no good reason for this.”

Beck said the shooting appeared to be “tied to a dispute over intellectual property.” Sarkar apparently felt that Klug had released some kind of information that harmed him, Beck said.

“That appears to be his motive,” Beck said. “When I say his motive, there’s nothing factual to this. We have discussed this with UCLA, and UCLA says there is no truth to this, this was a making of his own imagination.”

UCLA officials said they could not confirm whether there was a dispute or whether Sarkar, who attended the school between 2007 and 2013, had been flagged as a potential concern during his time there.

Social media postings by Sarkar, who moved to Minnesota after graduating from UCLA’s engineering school in 2013, showed him “bashing” the professor, Beck said.

“I know that … Sarkar, our suspect, had issues with his professors that were known to them,” Beck said. “But I don’t think that is a cause for somebody to believe they’re going to be a homicide target.”

Klug served as Sarkar’s adviser for his dissertation, which focused on cardiac issues and was approved in 2013. The dissertation includes a dedication: “In loving memory of my mother, Ira Sarkar.”

VICTIM DESCRIBED AS GOOD-HEARTED

The shooting at UCLA locked down the campus for two hours Wednesday morning, prompting a massive law enforcement response and forcing students to hide in rooms amid fears of an active shooter. Scott Waugh, the executive vice chancellor and provost, said the university would review its active-shooter protocols in the wake of the shooting.

A colleague on the faculty described Klug as sweet, gentle and good-hearted. Klug led the team that created a virtual heart, a supercomputer model realistic enough to test drugs and devices. Klug was doing research on developing drug strategies to treat a common and deadly type of heart disease and the mechanics of the heart.

In 1997, Klug graduated from Westmont College, a liberal arts school in Santa Barbara, California, with a bachelor’s degree in engineering physics. Westmont President Gayle D. Beebe said in a statement Thursday that Klug was remembered “as a gentle, kind person without a trace of arrogance.”

Klug went on to get a master’s degree in civil engineering at UCLA in 1999 and got his doctorate in mechanical engineering at the California Institute of Technology in 2004. Klug’s wife, Mary Elise, also graduated from Westmont and UCLA, according to those schools.

“I was a teaching assistant at Westmont and held help sessions for students. Mary Elise often sat in on them and told me I should be a teacher,” Klug said in a Westmont magazine alumni profile. “She kept talking about it.”

UCLA students organized a memorial Thursday evening for Klug, while the engineering school planned a vigil for Friday.

People who knew Klug remembered him Thursday as someone who spent years volunteering with a local little league team, describing him as dedicated to teaching people and helping them grow.

Alex Levine, a UCLA professor who had collaborated with Klug, called him a “decent and kind person” who loved his job, loved interacting with students and felt privileged to be a professor at the university.

“He was a soft-spoken person and in a world of large egos, he did not have one,” Levine said.

Levine called Klug an “excellent mentor to his students,” who got to know them personally and let them take the lead on their own projects. Klug was also an avid surfer when his children were younger, Levine said, and a Dodgers fan.

“Last time I saw him, he was showing me movies of his son pitching,” Levine said. “And he was telling me the technical details of how you plant your foot that I would never have known about.”