MARIETTA - Former Cobb 911 operator Julia Lynn Turner, who was convicted of murdering her husband and boyfriend using antifreeze, died early Monday morning in Metro State Prison in DeKalb County. Prison officials said the cause of death was still being investigated following an autopsy Monday afternoon.

Lynn Turner, 42, was serving two life sentences in prison, with no chance of parole, for the murders of her husband, Cobb County police officer Glenn Turner, and her live-in boyfriend, Forsyth County firefighter Randy Thompson, both of whom died from antifreeze poisoning.

Georgia Department of Corrections officials said Turner was found unresponsive in her cell on Monday around 7 a.m. Medical staff was unable to revive her and she was pronounced dead at 7:35 a.m. John Bankhead, spokesman for Georgia Bureau of Investigators, said the autopsy was complete, but toxicology tests are still pending. He did say there was no indication of foul play.

Lynn Turner's attorney, Vic Reynolds, said he received word of the convicted killer's death shortly before lunch on Monday, when one of her family members called his office.

"The only way that I can sum this up is that it's a tragic ending to a tragedy," Reynolds said. "I was floored when I heard it today. I just hope that everybody touched in the case will find some peace in all this."

Lynn Turner, who has been dubbed the "black widow," was first convicted of murder in May 2004 for the death of her husband, who died in 1995. At the time of his death, it was believed that he died of an irregular heartbeat.

In January 2001, Thompson, 32, her boyfriend and the father of her two children, was found dead. An autopsy of the firefighter's body revealed the presence of oxalate crystals in his bloodstream, which form when the body metabolizes antifreeze. Thompson's death was later ruled a homicide.

Following Thompson's death, GBI officials ordered the exhumation of Glenn Turner's body in July 2001. Officials also found the presence of oxalate crystals and his death was then ruled a homicide. Lynn Turner became the main suspect in both cases and she was indicted for the murder of her husband in November 2002 in Cobb County. The trial was later moved to Perry, Ga., because of pre-trial publicity surrounding the case.

In both cases, the prosecution claimed that Tuner had repeatedly poisoned her victims and that her motive was money and lust. According to court testimony, Turner was dating Thompson when she murdered her husband. Turner received more than $250,000 in insurance and Social Security benefits in the deaths of both her husband and Thompson.

Before the trial for Glen Turner's murder, Cobb Superior Court Judge James G. Bodiford ruled that the jury was allowed to hear evidence surrounding the death of Thompson, since there were enough similarities between Turner and Thompson's deaths - a move that Reynolds said made the case much more difficult to defend.

"In preparing a defense for that case, it became very obvious to us, when both murders were allowed to be presented, once that came in, it was tough sledding," Reynolds said Monday.

Both he and his law partner Jimmy Berry were retained when Lynn Turner became a suspect, and the two attorneys defended her in both murder trials.

Following her first murder conviction, Lynn Turner was indicted in Forsyth County in October 2004 on murder charges for the death of Thompson. That trial was conducted in Whitfield County, because of issues with finding an impartial jury in Forsyth. Also in October 2004, she was indicted in Gwinnett County on three counts of forging documents to obtain a loan to pay her legal bills.

In March 2007, Turner was found guilty of the murder of Thompson and sentenced to life in prison with no chance of parole.

Meantime, in May 2004, Reynolds and Berry filed a motion for a new trial based on the fact that the jury was allowed to hear information about Thompson's death and claiming that a move used by Cobb District Attorney Pat Head during his closing arguments was inappropriate. Bodiford denied the motion for a new trial in January 2006, which was upheld by the Georgia Supreme Court in February 2007. The Supreme Court's ruling stated: "Turner was intimate with both Thompson and Glenn, both men went to the hospital complaining of flu-like symptoms soon before they died, both men died from the unique cause of antifreeze poisoning, Turner was the last person to see either men alive, (and) both men died soon after Turner served them Jell-O."

Head, who prosecuted the case, defended his use of a poem called "The Prisoner," which was written in first person by a forensic scientist who had worked for the FBI on poisoning cases, and projected it above a large picture of Turner during his closing arguments. The poem, written by Dr. John Testrail, read in part, "My crime is quiet and well-thought out ... The evidence is really on my side for I count on you to bury my homicide ... I am a prisoner, can you catch me?"

Head said Monday of the case, "I put it across the top of the page with her picture underneath it. It is not uncommon in trials. It was a poem that was exactly in line with the facts of the case. There's nothing improper about doing that. It hadn't been done like that before. Six years ago, not a lot of people were using PowerPoint presentations; now I think almost all of my attorneys are using PowerPoints in all of their cases."

Head said the Turner case, which garnered national media attention and coverage on Court TV, was the first of its kind in the nation. Following the trial, he said, he remembered being very tired.

"We were working very long hours, I'm telling you all of us, and I'm sure that Jimmy and Vic were very tired when it was over," Head said.

When asked about his impression of Lynn Turner during the trial, Head said she seemed very unemotional.

"Something that I found remarkable when they read the verdict was that the expression on her face didn't change," the DA said. "She simply reached up and took her earrings off because she knew she was going into custody."

But defense attorney Reynolds said he saw a warmer side to Lynn Turner.

"It's like any other case when you defend an individual, you see a side of them that the public doesn't see," Reynolds said. "We saw a side of Lynn that was a loving mother. She loved her children very much - doted on them and bragged on them."

However, Reynolds said his impression did not diminish any verdict either juries handed down, nor did it justify Turner's behavior.

Reynolds said at the time of her death he believed Turner was still in the process of appealing her case in Forsyth County.