SALT LAKE CITY (ABC4) – Rachelle Arenaz left home one night and never returned.

What happened to the 16-year-old West High School student in 1979 still remains a mystery.

“This is the family picture,” said Jolene Arenaz as she pointed to a collection of pictures.  “This is me.  This is Rachelle.”

Arenaz and her son, Gilbert, recently met with ABC4’s Justice Files to revisit what happened to Rachelle in 1979.

“She was so pretty, so sweet and that’s heartbreaking,” said her mother.

The Arenaz family has waited for more than four decades to learn what happened to Rachelle.  It all began on September 15, 1979.  

“It was a Saturday afternoon and my daughter came in and she said she would like to spend the night with her friend Bridgette and I said no,” recalled Arenaz.

But Rachelle went out anyway.  According to her mother, Rachelle sneaked out the window as her younger daughter watched.  She left to go visit her teenage friend. But first, she stopped at her cousin’s house. 

“Her plans were to go to the dance,” her cousin Linda Homer said.  “Which friends, I don’t know.”

According to her cousin, there was a Mexican independence celebration at the Salt Lake Terrace Ballroom that night.  The Terrace which has since been torn down was located on Main Street between 400 and 500 South.

“She asked if I going to the dance tonight,” recalled Homer.

But Homer had no such plans and she said Rachelle remained at her home for several hours before leaving.

“Had I gotten the sense of urgency or fear or some basic sense of concern, I would have stopped and I would have listened to her and talk to her,” said Homer.  “Whether she made it to the dance or not I don’t know.  I don’t think any of us really know.”

It’s not until Jolene Arenaz’ younger daughter told her that Rachelle climbed through the window and left.  

Over the next four days, Arenaz became worried as Rachelle never returned.

By then, she learned her daughter met up that night with Bridgette Garcia, a school friend.

“I have no idea where they went to,” said the mother.  “I didn’t hear.  There’s conflicting stories.  I just know that Bridgette did not come home apparently for a week.”

The following week, with no sign of her daughter, Arenaz turned to Salt Lake police to file a missing persons report.  But she police claimed Rachelle did not the criteria to be called a “missing person.”

Instead, police called her a 16-year old “runaway girl,” according to a 1979 Salt Lake City police report.

The report also claimed that her mother said Rachelle “has taken up with some unknown person” and left town.

Police also found Bridgette Garcia and in the 1979 report they interviewed her “when questioned she “denies any knowledge of Rachelle’s whereabouts.” 

Arenaz also met with Garcia.

“She told me that somebody picked her up around Liberty Park,” the mother said. “I took Bridgette with me and she showed me some apartments.” 

But she said Garcia was evasive and changed stories.  The search near Liberty Park was a dead end.

In April, 1980, the family had ” not had direct contact” from Rachelle, according to a supplemental police report.

The report indicated the case was “closed.”

But Arenaz still would get periodic updates from a detective with Salt Lake police.

“He’d update and say ‘no, no bodies” have turned up any where, ‘there’s no sign of her,’” said Arenaz.

But a month later, May 13, 1980 a body was discovered near 2100 North and 4000 West in Salt Lake City.

The stories claimed the body was “badly decomposed” and the cause of death was “undetermined.”

“I turn the news on and they talked about finding the body of a young woman,” recalled Arenaz. “I watched them pick up a black body bag and I thought, ‘oh my gosh, oh my gosh.’”

Dental records helped prove the body was that of Rachelle Arenaz.  Finally, the family had an answer.  But who did this to her remained a mystery.

Rachelle’s death impacted the life of her younger brother Gilbert Arenaz. Wednesday night, as Rachelle’s story continues, Gilbert revealed it was the reason he became a police officer with Salt Lake City and eventually was promoted to the homicide division.