Los Angeles detectives were going through cold case files, following the arrest of a 72-year-old man suspected of being the city’s worst serial killer, for raping and murdering dozens of women decades ago. Police believe that John Thomas Jr is responsible for as many as 30 murders dating back to the 1970s and 1980s.

John Floyd Thomas Jr., 72, may have begun his killings as far back as 1955 and he could be one of the worst serial killers in United States history, according to Los Angeles Police Chief William Bratton.

Thomas was arrested on March 31 when police linked a DNA sample taken from him to the crime scenes of two women murdered four years apart in 1972 and 1976. Evidence linking him to three other murders has also been found. “Thomas, at this time — and we think this is probably going to expand — is also suspected in as many as 25 other murders that occurred in the Southland in the 1970s and 1980s,” Los Angeles Police Chief William Bratton said, “We have not yet reached the depth of what he’s done“.

Thomas, who sits in a Los Angeles jail, has been charged with two killings — in 1972 and 1976 — but prosecutors will likely add more cases when he faces arraignment on May 20.

While Thomas was arrested “a number of times between 1955 and 1978″ for sex crimes and burglaries, detectives did not have the technology to identify him as a suspect when the region was terrorized by a series of killings then blamed on the “Westside Rapist,” Bratton said.

As part of an ongoing Los Angeles Police Department program to collect DNA evidence from convicted sex offenders, officers asked Thomas for a DNA swab – and that’s when they first matched his DNA to rape kit evidence collected from first two victims, and investigation went on.

“Because of Thomas’s criminal background, the close proximity of his homes to murder locations, similar victim descriptions [white elderly females] and other evidence that suggests the type of modus operandi used by the suspect, detectives strongly believe Thomas is very likely the suspect in ‘The Westside Rapist’ cases,” a police statement said.

By most available accounts, John Floyd Thomas Jr. spent the last two decades living a relatively quiet life:
“He always had a smile on his face. He was placid, congenial and affable, a pleasant fellow who, if the allegations are true, may in fact be a monster,” said Earl Ofari Hutchinson, an L.A. community activist who once worked with Thomas. “It almost takes your breath away.”

While he served about 12 years in prison between 1955 and the late 1970s for his previous convictions, he has no record since his last arrest in 1978, police said.

Deputy Chief Beck said the growing use of DNA databases and computers to match them to crime evidence will likely lead to more cold case killers being identified.

-article by Alan Duke and Andrew Blankstein rewritten and adapted by admin-