San Joaquin County prosecutors have rearrested a man in connection with the 2019 disappearance of California teenager Victoria Marquina, announcing an indictment charging him with murder and alleged sex crimes with a minor.
Background
Victoria Marquina was 16 years old when she vanished from Amador County in October 2019. Joshua Anthony Martinez, who was 21 at the time, was in an unlawful dating relationship with the teenager, according to the Amador County District Attorney's Office. Martinez admitted to authorities that he dropped Marquina off in Sutter Creek, the last known location where she was seen alive.
Following her disappearance, Martinez fled to Mexico. He was eventually extradited back to the United States and arrested in connection with the case in October 2019. However, Martinez was later released from custody after prosecutors determined they needed additional evidence to pursue charges.
Marquina's body has never been found, but her vehicle and cellular phone were located in San Joaquin County shortly after her disappearance. The Amador County Sheriff's Office stated at the time of Martinez's first arrest that it possessed circumstantial evidence allegedly proving he killed her.
The Investigation
In 2025, the San Joaquin County Sheriff's Office established a new cold case task force to review unsolved cases, including Marquina's disappearance. The task force reexamined evidence and collaborated with the Amador County District Attorney's Office.
Earlier this year, the Amador County DA's Office authorized prosecution in San Joaquin County under jurisdictional laws that allow cases spanning multiple counties to be tried there. The case was presented to a criminal grand jury in Stockton, which returned a true bill of indictment on Monday.
Martinez was rearrested and indicted in San Joaquin County court. According to the jail booking log, he is facing charges of murder along with several alleged sex crimes with a minor. He is being held without bail.
San Joaquin County District Attorney Ron Freitas met with Marquina's mother shortly after taking office. "She told me her heartbreak and not knowing where her daughter was and not having the person that killed her being held accountable," Freitas said outside the courthouse. "It's weighed heavily on me and it's one of the things that I've thought about almost every single day since taking office."
Key Takeaways
- Victoria Marquina was 16 years old when she disappeared from Amador County in October 2019
- Joshua Anthony Martinez was 21 at the time and was in an unlawful dating relationship with the teenager
- Martinez fled to Mexico after Marquina vanished and was later extradited back to the U.S.
- He was originally arrested in 2019 but released from custody due to insufficient evidence at the time
- A San Joaquin County grand jury returned a true bill of indictment on Monday charging Martinez with murder and alleged sex crimes
- Marquina's body has never been found, but her vehicle and phone were recovered in San Joaquin County
- A cold case task force formed in 2025 reviewed the investigation before authorizing the new prosecution
What's Next
Martinez remains in custody without bail in San Joaquin County. The case is proceeding through the court system, and no trial date has been set. Investigators continue to seek information about Marquina's whereabouts, with her mother urging anyone with knowledge to come forward.
"If you know something, if you heard something, if you know where my daughter is, please communicate," Victoria's mother, Blance Valencia, said.