Green River Serial Killer's Final Victim of 49 Women and Girls He Murdered Identified as 16-Year-Old Tammie Liles

The victim's remains were known as “Bones 20” until being identified, authorities have confirmed

The last known remains — labeled “Bones 20” — linked to the Green River killer have been identified as belonging to a teenage victim, according to breakthrough reports.

The victim has been named as 16-year-old Tammie Liles, who was murdered by serial killer Gary Ridgway in 1988, the King County Sheriff’s Office confirmed in a news release, per NBC, The Seattle Times and Everett Herald.

According to local media, the victim — who disappeared in the summer of 1983 — was from Everett, Washington, north of Seattle.

Ridgway, 74, has been convicted of murdering 49 women and girls during the 1980s and 1990s in Washington. In addition, he is believed to have killed over 90 women and girls between 1982 and 1998.

He is currently serving several consecutive life sentences in Washington State Penitentiary in Walla Walla, Washington with no chance of parole.

Liles was previously identified through dental records after part of her remains were discovered in Oregon, per the King County Sheriff Office's news release.

As part of his plea deal to avoid the death penalty in 2003, Ridgway led investigators to the locations where he buried one of his victims by Green River — inspiring his nickname as the Green River Killer — in south King County. There, 23 human bones and teeth were uncovered and listed only as “Bones 20."

After two decades, Liles was able to be identified as the victim after examination of DNA extracted from the skeletal remains by Othram Inc., a forensic laboratory specializing in difficult DNA cases.

In 2022, the lab “tentatively” identified Liles as the victim after initial investigation, according to the release.

“Authorities contacted Liles’ mother, and using her reference sample, scientists were able to identify Liles through traditional STR and mitochondrial DNA testing,” according to DNASolves.com, per Everett Herald.

“It’s an immense feeling of satisfaction that in this case, that started in the early 80s, we are able to identify all of Gary Ridgway’s victims, all 49 of them,” Sheriff’s Office spokesperson Eric White said of the final breakthrough in the case,  per NBC.

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PEOPLE has contacted the King County Sheriff's Office for further comment.

This breakthrough in the case comes after 15-year-old Lori Anne Razpotnik was identified as another victim of Ridgway’s from remains known as “Bones 17” in late 2023, reported Everett Herald. 

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