ATLANTA - The results of new DNA testing released Monday raised fresh concerns about the conviction of a Georgia inmate sentenced to death on charges of strangling three elderly women with their own stockings in the 1970s.

The results of the Georgia Bureau of Investigation's testing show that Carlton Gary's DNA did not match samples from one of the victims. A test for another victim was inconclusive, while samples from the third victim were not tested.

But prosecutors point to a fourth test that links Gary's DNA to a fourth woman, Jean Dimenstein, who was raped and killed in 1977. Prosecutors have long accused Gary of the woman's death, but didn't ask jurors to convict him at his 1986 trial.

Defense attorney Jack Martin, who said he plans to request a new trial, said the results of the tests raise "grave doubts" about the case against his client.

"We've been saying this for years now and it turns out to be true: He really wasn't the person who committed these crimes," Martin said. "The real perpetrator is still out there. What are they doing to catch the real murderer?"

Muscogee County District Attorney Julia Slater said she has appointed a special prosecutor to handle the case and is requesting a status hearing in Gary's case to discuss the DNA results. She said the results show there is "no denying his culpability" in the crime.

"I expect the court will look at this finding in light of all the other overwhelming evidence of Carlton Gary's guilt," she said.

Gary, known as the Columbus "Stocking Strangler," was just three hours from execution in December 2009 when the Georgia Supreme Court ordered a judge to determine if authorities should conduct DNA testing of hair, semen and fingernail scrapings that wasn't available when he was convicted in 1986.

A judge allowed the testing in February, and investigators spent months analyzing the results.

The slayings terrified fearful Columbus residents, who barricaded themselves inside their homes as the spree claimed seven victims who all fit an apparent pattern: They were elderly white woman who lived alone.

Then it stopped as suddenly as it started.

The crimes remained unsolved for six years until authorities linked a pistol stolen from a home in the Columbus area in October 1977 to Gary, a charismatic ex-convict who had escaped from prison twice. He was arrested in May 1984, and authorities said he soon confessed to involvement in the rapes and slayings.

But Gary contended during his trial that another man committed raped and killed the women. And his attorneys noted that tests of blood evidence and hair samples taken from the crime scenes at the time were inconclusive.

Prosecutors, though, showed fingerprint evidence that put Gary at four of the crime scenes, and a surviving victim testified that she recognized Gary when she saw him on television news reports. They also said he confessed to police that he was at the scene of the murders.

Gary had a lengthy rap sheet when he was nabbed. He had spent time behind bars since he was a teenager, and he escaped prisons in upstate New York and South Carolina. But he was also known as a talented musician and ladies' man who was handsome enough to model at a local clothing store.

A jury convicted Gary in August 1986 of three counts of malice murder, rape and burglary for the deaths of Florence Scheible, 89; Martha Thurmond, 69; and Kathleen Woodruff, 74. He was sentenced to death on all three counts of murder a day later.

The DNA tests of a semen sample taken from Thurmond do not match Gary, Martin said. He said that DNA tests of semen samples from Woodruff were not conclusive and that no DNA testing was conducted in Scheible's case because the sample was deemed problematic.

Slater urged residents not to read too much into the results of Thurmond's test, which she said could have been tainted by contamination or degradation.

"It is important to remember that this finding does not in any way exonerate Carlton Gary from the Thurmond incident or any other incident," she said.

Other authorities are unswayed by the findings. Columbus Mayor Jim Wetherington, who was the city's police chief at the time of Gary's arrest, said he's still confident that authorities arrested the right guy.

"We were convinced that we had the right person, and I don't really have any doubt in my mind that he was the guy who committed the crime," he said. "And there's still no doubt in my mind."