In their first interview since police say their daughter was assassinated over the weekend, the parents of Minnesota lawmaker Melissa Hortman described the "mind-numbing pain" they are going through as they relive the events of Saturday morning.

Further, Hortman's mother, Linda Haluptzok, told CBS News that "the division has to end."

Linda and her husband, Harry Haluptzok, gave the interview at the home of their late daughter Melissa and her husband, Mark, as they stopped to pick up clothes for the couple to be buried in.

Police say Vance Boelter shot and killed the Hortmans after first shooting and wounding state Sen. John Hoffman and his wife about 9 miles away early Saturday.

"We knew that they had been shot, but we couldn't find out where they were. We chased around hospitals, and we couldn't find them," Linda Haluptzok told CBS News.

"We looked at each other and realized the reason they weren't in the hospital was because they weren't alive. And that was hard to figure out, and then we got the call," Harry Haluptzok said. "It was horrible."

Boelter was arrested Sunday night after a two-day manhunt. The killings have been described by law enforcement as politically motivated, prompting Linda Haluptzok to say, "The division needs to end."

"There was a time, not that long ago, when we could all work together ... and whatever steps we need to get back there, I don't know how we do it, but we all have to try. And if it's one person at a time, we have to make it happen, and we can't let hatred and division rule the actions that are happening now," she said.

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