MINNEAPOLIS (WCCO) – Authorities in Arizona say an arrest has been made in the 2015 fatal assault of a woman from Minnesota.

Allison Feldman, a 31-year-old medical sales rep, was murdered in her Arizona home on Feb. 17, 2015. Authorities said she died from blunt force trauma.

Scottsdale Police announced Tuesday 42-year-old Ian Mitcham was arrested and will be charged with first-degree murder in Feldman’s death.

At the time, police were investigating if she might have been the victim of a random attack. Her boyfriend came home to discover her body.

“I have always kept hope alive, but it’s gotten harder,” said Kelly Weinblatt, Feldman’s sister.

After more than three years, she finally heard the words she’s been desperately waiting for, regarding the unsolved murder — that a suspect was arrested.

“It’s been just very overwhelming. Like, it’s kind of hard to believe that this just happened,” she said.

Investigators believe Mitcham is the man who killed Feldman in her home in 2015.

“We exhausted, over that three-year period, every lead we had,” said Asst. Chief Scott Popp, Scottsdale Police Department.

Investigators found DNA evidence at the scene. Recently, they used familial DNA testing. They were able to connect the sample at the scene to a sibling of Mitcham’s who was already in the prison system.

Weinblatt said her father — who lives in Excelsior — learned of the breakthrough first, then told her in person.

“He pulled me aside and said ‘I talked to the police today, and the familial DNA results are in, and there’s a hit.’ And I — it just, kind of was a blur after that,” she said.

Weinblatt says she thinks about her sister daily, even wanting to visit her grave site and tell her of the arrest. The search for a suspect is finished, but justice through a murder conviction awaits.

“Certainly knowing that he’s not walking the streets tonight and living his life is somewhat comforting for us,” she said.

Weinblatt said her family keeps in regular contact with Scottsdale Police and said they’ll be flying out there in the near future as the court proceedings begin. She also wanted to say thank you to Scottsdale Police, the Arizona Department of Public Safety for the DNA testing, and the media for keeping her sister’s story in the spotlight.

There’s also a foundation set up in Feldman’s name, which helps fund the study abroad program at the University of Arizona — something Feldman was passionate about. Since the arrest, it has recently gotten more donations.