Sweetwater County authorities say Rodney Alcala, the so-called "Dating Game KIller," won't be extradited to Wyoming to face charges in connection with a murder case from the 1970s.

Sweetwater County Attorney Daniel Erramouspe says Alcala is hospitalized in a California prison and is in such bad health he can't travel. Alcala has already been sentenced to death in California for several murders.

Investigators believe Alcala killed 28-year-old Christine Ruth Thornton of San Antonio, Texas and left her body in a remote area northwest of Granger, a small community in western Sweetwater County in 1977.

Thornton's body was found by a rancher in 1982. Investigators at the time said the evidence at the scene had been broken down over the years, but they were able to say the person had been  the victim of a homicide. But the didn't know who the victim was.

In 2013, Detective Jeff Sheaman of the Sweetwater County Sheriff's Department re-opened the investigation into Thornton's killing. A tissue sample from the victim was sent to the North Texas Center for Human Identification for mitochondrial DNA testing and inclusion in the National Missing and Unidentified Persons System (NamUs).

That system works to identify missing people through a variety of methods. One way is to compare DNA samples from homicide victims to living relatives of people reported missing.

In 2013, NamUs was able to tell Sweetwater County investigators that the body found in 1982 had been that of Christine Ruth Thornton. In 2013 a relative of Thornton's was going over some photographs that had been found in Alcala's possession in 1979 and identified one of them as a photograph of Thornton that had been taken not far from where her body was eventually found.

Alcala had been convicted in 1980 for the murder of Robin Samsoe. In 2010, he was found guilty of the murders of four other women and was sentenced to death by a California jury.

He was known as "The Dating Game Killer" for his 1978 appearance on the popular television show. Investigators think he may have claimed as many as 130 victims across the country.