Alaniz was last seen in El Paso, Texas on March 7, 1987. She went out to play video games and never returned to her residence in the northeast part of the city. She has never been heard from again. That same year, several other females disappeared from El Paso, and most of them were later found murdered and buried in the desert. The victims were all young, mostly in their teens and twenties. Alaniz and another girl, Cheryl Vasquez, are still missing, but presumed to be homicide victims as well.

David Leonard Wood, a serial rapist who was paroled in January 1987, was later convicted of murdering six of the El Paso victims. He has not been charged in connection with Alaniz's case, however, and it remains unsolved.