“He was just so incredibly intelligent but then so incredibly passionate at the same time,” Elaine Karaelias tells PEOPLE. “If I were to be a professor, he’s the example that I’d want to follow.”
Klug, 39, was shot and killed by a former doctoral student inside his small office in UCLA’s Boelter Hall before turning the gun on himself. The shooting set off a campus-wide lockdown until authorities confirmed the murder-suicide.
Karaelias tells PEOPLE that Klug, a married father of two, kept a picture of his wife and children on his desk, and was impressed with the way he balanced his duties as a family man and professor.
“I was always astonished about how he drove up to UCLA every day and then had time to spend time with his family and coach [his son’s] baseball team,” she says of the El Segundo resident, who served as a Little League coach.
“He always came off as a huge family man,” she adds.
Karaelias met Klug when she enrolled in his cellular mechanics course in 2009 through an extension program. In 2010, she enrolled in a master’s program – with Klug as her advisor and mentor.
“I pretty much owe my graduate degree to him,” she tells PEOPLE.
Over the next three years, Karaelias studied under Klug as she divided her time between school and working at St. Jude’s Medical.
She says Klug’s door was always open and that he cared for “each and every student,” giving them extra time for projects and making his complicated lessons easier to understand for everyone.
“He’s always very inspiring,” she remembers. “He is the type of educator that would relate to his students and get them to trust him and respect him.”
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Police identified Klug’s killer as Mainak Sarkar, 38, a former doctoral student who had compiled a “kill list” that included Sarkar’s wife, who was later found dead in their Minnesota home.
“That s just the hardest part out of all of this,” Karaelias says of Sarkar’s kill list. “Who would want to target this person that is so kind and generous and brilliant and could contribute so much to the world and already has? How is that possible?”
Sarkar’s motive for killing Klug is not clear. However, police believe the shooting could be tied to a dispute over intellectual property. Multiple reports claim Sarkar blamed Klug for stealing a computer code and giving it to someone else.
While Karaelias says she recognized Sarkar’s face from passing him in the hallways years ago, she tells PEOPLE she doesn’t remember anything else about him.
Karaelias, who is a quality engineer at a medical device company, says she kept in occasional touch with Klug after graduating in 2013: “He was my advisor, my mentor, my role model.”
A GoFundMe page to raise money for Klug’s family has already garnered more than $80,000.