(CNN) -- The remains of two bodies recovered last week based on maps provided by a California death row inmate have been identified through DNA testing as those of two women, Chevelle Wheeler and Cyndi Vanderheiden, investigators said Wednesday.
Wesley Shermantine, one of two "Speed Freak Killers," is awaiting execution after being sentenced to death in 2001 for four homicides.
Shermantine provided maps and letters to a reporter at The (Stockton) Record newspaper, who then forwarded them to investigators, said Deputy Les Garcia of the San Joaquin Sheriff's Office.
Searchers, aided by dogs, found the human remains while using the maps to search sites in San Andreas in Calaveras County, including property that once belonged to Shermantine's family.
A forensic dentist using dental records made preliminary identification of Wheeler, who disappeared in the 1980s, and Vanderheiden, but the DNA testing confirmed it, the San Joaquin County Sheriff's coroner said Wednesday.
Authorities are looking into whether there could be more buried victims.
They set up a hotline for relatives of missing persons who may have fallen victim to Shermantine and another man, between the mid-1980s and 2000, Garcia told CNN.
The tedious search for additional victims is primarily focused on a 19th-century well near Linden, about 30 miles from where the two women's remains were found, Garcia said. Linden is 55 miles south of Sacramento.
Besides finding hundreds of pieces of suspected human bone, investigators are unearthing purses, belts, coats, shoes and rings.
Bounty Hunter Leonard Padilla told CNN that he promised Shermantine $33,000 for information leading to the remains of Wheeler and Vanderheiden.
About $18,000 was for the inmate's restitution and $15,000 was for headstones for the graves of Shermantine's parents, he said.