LOS ANGELES (NewsNation Now) — Los Angeles police released surveillance video showing the moments after a newly identified suspect allegedly stabbed a UCLA student to death at random.

Shawn Laval Smith, 31, is suspected of killing Brianna Kupfer, 24, at the Croft House furniture store where she worked in L.A., police said Tuesday. The reward in the case has now topped $250,000 and a warrant is now out for his arrest. Smith should be considered armed and dangerous, LAPD said.

Police say newly released surveillance video shows Smith inside a 7-11 store about 30 minutes after the killing last week. He paid for an item and walked away.

Kupfer was a design consultant at Croft House. She was working on her graduate degree in architectural design at UCLA. Her heartbroken family includes her parents and three siblings.

“It’s unfathomable feelings, just like you want to go away,” her father, Todd Kupfer, said. “Soon you want yourself to go away because you just don’t want to feel it anymore.”

Police also said Kupfer had texted a friend about getting “bad vibes” from a man in the store, but that friend didn’t see it in time. Kupfer was working alone at the time of the attack.

“To me, she’s the epitome of good, like my other children,” Todd Kupfer said. “And the epitome of evil just takes that away from us.”

Police said they believe Smith was homeless but is “likely” to use public transportation.

Nearby business owners declined on-camera interviews with NewsNation, but said some people who are homeless do come into their stores. Some of the businesses are appointment only.

“They [police] had stated that he had walked into a couple of other businesses prior to,” security consultant Bryan Ferguson said on “Morning in America.” “It could have been just casing them to see if he can find somebody that was by themselves. More than likely it was a crime of opportunity for him and he found a location that had just one person there.”

The Associated Press and NewsNation affiliate KTLA contributed to this report.