(NEW YORK) -- Investigators in Baton Rouge, La., say they may have cracked a 28-year-old cold murder case after re-arresting two suspects who were originally linked to the 1984 disappearance of a Louisiana businessman.
Leila Mulla, 57, was arrested by Louisiana investigators in New York City, and Ronald Dalton Dunnagan, 64, was arrested in Bossier City, La., Monday. The missing man, Gary Kergan, was last seen alive at Mulla's Baton Rouge home Nov. 29, 1984, police say.
Mulla, who, according to the Queens (N.Y.) District Attorney's office is now a registered nurse, was seen with Kergan, 29, on that night in 1984 at a Baton Rouge nightclub. Kergan was seen wearing flashy jewelry and carrying a significant amount of cash when they left in his Cadillac, police say.
Kergan and his brother owned a string of Sonic fast-food restaurants in Louisiana.
Baton Rouge Police Lt. Don Kelly, who was then a reporter in the city before joining the police force, said Kergan was specifically targeted by Mulla and Dunnagan.
"[Kergan and Mulla] met at the strip club. They [Mulla and Dunnagan] were robbing him of jewelry and cash," he told ABC News. "He [Kergan] flashed jewelry and money, drove the big Caddy....I don't know about their [Mulla and Dunnagan's] relationship, whether they were dating...or mentor-mentee."
Kelly said that when investigators searched Mulla's apartment at the time, there was blood and signs of an effort to clean it up.
Kergan's car was later found abandoned in Metairie, La. A significant amount of blood was located in the trunk of the car, Kelly said, but it could not be determined at the time whether it belonged to Kergan.
"Of course, speculation was that [the blood] was Kergan's. But the technology didn't exist, with DNA testing, to establish that. And his family didn't know his blood type. It made it almost impossible," Kelly said.
Mulla, an exotic dancer at the time, moved out of the apartment within a few days of Kergan's disappearance, Kelly said. She and Dunnagan went to Las Vegas, where they were arrested weeks later.
Investigators had also obtained Mulla's diary, in which she outlined a plan to rob Kergan, Kelly said.
After their arrest in December 1984, Mulla and Dunnagan were charged in connection with Kergan's death. Although they had a timeline of events placing Mulla with Kergan on the night he was last seen, and evidence of a possible crime in her apartment, it wasn't enough, Kelly said. With only circumstantial evidence against the two, the district attorney opted not to prosecute.
Kergan's body has not been found. He was declared legally dead by the courts in 1986. But investigators were able to make an arrest in the nearly 30-year-old murder case when, as part of cold case review, the blood in the car was re-examined.
In March of this year, Baton Rouge police placed Det. John Dotchier in charge of re-examining the department's hundreds of cold cases. Kergan's death became the first one in which the enthusiastic detective got a break when blood from Kergan's Cadillac was re-tested at the Louisiana State Police Crime Lab. DNA analysis showed that the blood belonged to Kergan.
"We've got hundreds of unsolved cases, and this one was looked at this year," Kelly said. "When he saw this one with the blood, he could have swung and missed. It's the first one he's solved."
Kelly said he district attorney's office believes that it now has enough evidence to convict Mulla and Dunnagan.
He has been charged with first-degree murder, she has been charged with second-degree murder and both have been charged with criminal conspiracy and simple robbery. They won't be arraigned until they are returned to Baton Rouge to face formal charges.
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