WACO, Texas (KWTX) – A retired Waco man remains in the McLennan County Jail after the Texas Rangers cold case unit and west coast investigators linked him through a DNA database to the murders of prostitutes in East Texas and California 30 years ago.

Douglas Thomas, 67, was jailed this week under $2 million bond on a murder warrant from Titus County that charges him in the April 1992 death of Shenda Denise Hayes, according to a search warrant affidavit filed Wednesday by Texas Ranger Danny Briley.

The Ranger, who said in the affidavit that he investigates serial murders as part of the cold case unit, also alleged that Thomas was linked by DNA to the March 1993 murder of Sherri Herrera in Riverside County, California. Both women were described in the affidavit as “known prostitutes.”

Briley, the lead investigator in the 2013 shooting death of “American Sniper” author Chris Kyle, obtained a search warrant from 54th State District Judge Susan Kelly to extract a DNA sample from Thomas at the McLennan County Jail. Court documents show Briley took four swabs from Thomas’ mouth to get saliva samples.

Thomas was linked to the two murders by DNA samples from the crime scenes that had been uploaded years ago into the Combined DNA Index System, a national DNA database maintained by the FBI known as CODIS.

According to the affidavit, Hayes’ body was found near a rest area along Interstate 30 near Mount Pleasant in Titus County. An investigation showed she had been strangled “with a device made of wire and cord in a manner to control the victim,” the records state. She was found partially clothed with evidence of sexual assault.

Swabs taken from her body were uploaded into the DNA database in 2004, the Ranger said in the affidavit.

Mike Thompson, an investigator in the…