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San Mateo County 1992 cold case murder closed after suspect dies in Merced Co.

Gregory Marc Riviera had been sought in the killing of 25-year-old Juliette Rivera

The San Mateo County Sheriff's Office on Tuesday announced the closing of a 30-year-old murder case after investigators determined the lone suspect they were seeking had died elsewhere in the state earlier this year.

Gregory Marc Riviera had been sought in the killing of Juliette Rivera, a 25-year-old woman who was found in July 1992 by a farmworker near an irrigation pond in a coastal, unincorporated part of the county, according to the Sheriff's Office.

Rivera, an Alameda resident, was an acquaintance of Riviera and Alameda police interviewed him about her disappearance. Sheriff's officials said numerous inconsistencies in his statement led detectives to suspect he was involved in her disappearance.

In August 1992, a warrant was issued for Riviera's arrest on suspicion of the killing, but he had fled his apartment in Alameda days earlier and remained at large for years.

Then on May 12 of this year, the Sheriff's Office received a call from the Merced County coroner's office about a local transient who had died on Jan. 29, and fingerprints identified him as Riviera, who coroner's officials saw had the still-active warrant for his arrest in the killing.

Investigators confirmed it was Riviera who died, and that he had a brother whose daughter said the two brothers had used each other's identities for the past 30 years to elude law enforcement. As a result, the case was closed, according to the Sheriff's Office.