Cold case arrest culminates decades of detective work and collaboration

PHOENIX - The Elena Lasswell murder case took a step forward this week as police took her alleged killer into custody, The case spanned two decades, as the 15-year-old girl was murdered in 2004.

Now, Detective Dominick Roestenberg, who was lead detective on the case, is no longer haunted wondering if a suspect will have to answer to the crimes. Same with her family.

"It was a really, really special day," Det. Roestenberg said.

Roestenberg has been determined to find justice for Lasswell and her family since taking over her murder case several years ago.

"When I got involved, there was another detective in the cold case. He had been working the case as well. I remember when he left he said, ‘Dom, this case means a lot to me so please give me your word,’ and I said, ‘absolutely,'" Roestenberg said.

Cold case suspect found by "thinking outside the box"

Sergio Reyes was a lead suspect when the case began, but detectives didn’t have enough to indict him. Roestenberg, however, says collection of evidence at the initial crime scene was crucial.

"The work they did in 2004 really helped us to get to the point where we are now," Roestenberg said.

"There was some damage to the room. It looked like some type of struggle had taken place inside the room," he said. "The window was open. So we feel that the perpetrator probably left through that window."

READ MORE: Arrest made in cold case murder involving Phoenix girl

"Thinking outside the box, we were able to locate a family member of Sergio," he added. "We voluntarily collected their DNA, per consent, and we were able to compare the family member’s DNA to the DNA at the scene."

U.S. Marshals assist in arrest and extradition

Then came the challenge of getting Sergio extradited from Mexico where he had fled.

Roestenberg said U.S. Marshals from the Phoenix field office helped bring him back to Arizona.

"To identify and locate and apprehend somebody in another country presents numerous challenges. My hat goes off to them. Without them, I feel confident that Sergio would never have been brought back to justice," he said.

Emotional anniversary

July 10 - exactly 20 years to the day that Elena was killed - Roestenberg was able to share that news of justice with her loved ones. It was an emotional moment for the detective and her family.

"Tremendous amount of gratefulness to Phoenix PD, to Detective Roestenberg, to the Marshals, to everyone, to the extradition attorney. I mean they just kept going," Katie Tourville, Elena's aunt said.

Getting to call Elena's loved ones and tell them the news of Reyes' arrest was always the only option.

"I hate the word closure because you never really get closure when you lose a loved one like this, but it gives them some semblance of relief knowing that the person responsible is gonna be held accountable," he said.

"I’ve been talking to some of the family members now for gosh, six, seven years so we’ve gotten close over the years. I’ve tried to keep them updated as far as the status of the case but it gets frustrating. There were some highs and lows but finally making the call both to her father and her aunt made it all worthwhile."

What's next?

Reyes is currently being held on a $1.5 million cash bond.

Roestenberg said many suspects do flee to other countries, and he encourages people who may have information in those cases to come forward through the Silent Witness Program so detectives can connect with law enforcement in those other countries.

You can stay anonymous and reach Silent Witness at 480-WITNESS.