Justine Damond's fiancé describes his last conversation with her minutes before her death

Justine Damond's fiance calls for change

The fiance of an unarmed woman killed by a former Minneapolis police officer said he wants police nationwide to learn from the case. Don Damond told "CBS This Morning," "This is a policing issue," in his first sit-down interview since former Minneapolis police officer Mohamed Noor was found guilty last week of murdering Justine Damond nearly two years ago.

"I cannot even still get my arms around how this could happen," Damond said.

In what would be their final conversation, Justine called Don on the evening of July 15, 2017, while he was in Las Vegas for business. He said she was concerned she had heard a possible sexual assault near their home.

"My first thought was, 'I want her to be safe,'" Don Damond said. "And so I said, 'I think just stay put and call 911 and then call me back.'"

Noor and his partner responded to Justine's call. While searching for a suspect from inside their patrol car, Noor testified that he heard a loud slap on the driver's side of the vehicle and shot Damond from the passenger seat, out of fear for his partner's life.

"Probably six, seven minutes later, I text her having not heard from her," Don said. "I said, 'Tell me what's going on.' At this point, she was already gone."

Don and Justine were just four weeks away from being married when she died. Noor is facing more than 15 years in prison after being convicted of charges including third-degree murder.

Don said he broke down crying after the verdict was read.

"It was the acknowledgment that what we know is how tragic this is, how wrong this is, how unjust this was."

Calling for change, Don is hoping police can learn from his heartbreak.

"I would like the Minneapolis Police Department to go back and consider what- how officers are trained," Don said. "I can understand where Black Lives Matter is so angry because you can see the unjustified shooting across this nation, but this is a blue issue."

The case is not the first deadly police shooting in Minnesota to gain national attention.

In 2016, Jeronimo Yanez, a police officer in a St. Paul suburb, shot and killed 32-year-old Philando Castile during a traffic stop.

A jury eventually acquitted Yanez of all charges, inciting protests across the Twin Cities.

Minneapolis city leaders, including the mayor and police chief, acknowledged the police department's training and policies need improvement.

"First and foremost in my vision for the department moving forward is sanctity of life," Minneapolis Police Chief Medaria Arradondo said on Friday.

Damond hopes that progress isn't just confined to Minneapolis.

"How can what was learned here be taken to change and address policing in this country? There needs to be changes made so that no one has to go through this. That no one ever has to experience what we experienced," Damond said.

Justine's family filed a civil rights lawsuit seeking more than $50 million from Minneapolis.

The city settled with the family for $20 million, two million of which will go to a fund aimed at addressing local gun violence.

Noor's attorneys have not yet announced whether they will appeal his conviction.