Anaheim detectives are searching for clues in the murder of a young woman on the 20th anniversary of her disappearance.

The Police Department announced Tuesday, July 2, it was once again looking into the case of Mariana Tapia, whose decomposed body was found in a brushy area in a shallow grave in Anaheim, and are asking the public for any witnesses to come forward.

“It’s one of those cases that has been worked constantly over the years,” Sgt. Daron Wyatt said. “Whenever there’s a new advancement in technology, we’ll send more information over to the crime lab.”

A suspect has not been identified.

The 18-year-old Anaheim woman went missing after going to a friend’s birthday celebration at El Rodeo nightclub in Pico Rivera. Tapia was last seen dancing with men inside the club.

Her body was found more than a month later, on Aug. 22, 1999 buried near Gypsum Canyon and Santa Ana Canyon roads. An Irvine Co. employee, checking on a company fence, found the body.

The mother of a 4-year-old girl, Tapia had died of at least one gunshot wound.

Detectives have re-examined DNA and ballistic evidence and hope witnesses who previously did not come forward will now tell their stories.

“Early in the year 2000, a woman called detectives and provided specific information about Mariana’s murder,” Sgt. Jeff Mundy said.

The caller did not provide her name.

“We are asking this woman to have the courage to call us again, so we can bring justice to Mariana and closure to her family,” Mundy added.

Anyone with information about the case was asked to call Mundy at 714-321-3669.