Sgt. Tony Turnbull of the Sacramento County Sheriff's Office reports that Mejia was the victim of a homicide.
The Sacramento State graduate's body was found just before 7 p.m. Thursday off the roadway near Watt Avenue and Dyer Lane. An autopsy revealed that she died after sustaining a gunshot wound.
One of Mejia's roommates, who is in his mid-20s, is currently being held by police as a person of interest. He was arrested on suspicion of unrelated weapons charges, according to Turnbull.
It is possible that a weapon found on the roommate could have been used in the homicide.
It is unknown if multiple people were involved in the murder or the eventual dumping of Mejia's body.
Mejia's other roommate reported her missing Tuesday after Mejia left their north Sacramento home on Pepperwood Knoll Lane around 9 a.m. and never returned. She reportedly had a doctor's appointment in Stockton that same day that she did not show up to.
Monday Mejia left her family's Stockton home to drive back to Sacramento. She was scheduled for a shift at her job at Nordstrom's at the Westfield Galleria mall in Roseville. She never showed up for work and her credit card was later located in the Nordstrom's parking lot.
Investigators located the 28-year-old's Honda Civic Wednesday in the Arden-Arcade area. Officials believe the car was not brought there by Mejia.
The Sacramento County Sheriff's Office is still searching for further witnesses or anyone with information surrounding this incident.
The money on Mejia's Go Fund Me page is now being used for funeral services.
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