Updated

A news station is reporting a new development in a cold case that has stymied investigators in northwest Florida for nearly three decades.

WTVY in Dothan, Ala., reports that a retired Florida sheriff has agreed to help investigate the high-profile killings of Robert and Kathryn McRae, who were shot execution-style in their Graceville home on Jan. 27, 1989.

“We've got probable cause to arrest a lot of people but we can't because we don't have that bit of information that would help do it," former Bay County Sheriff Frank McKeithen told a news conference Thursday in Marianna, Fla.

Jackson County Sheriff Lou Roberts is overseeing the McRae investigation. He and McKeithen are longtime friends.

The station reports that there has been speculation for years that the McRae murders may be linked to an Alabama cold case.

Acie and Carolyn Worthy were found dead in their Tuscaloosa County home after it had been set on fire. Investigators say the couple was shot dead when they arrived home from evening church services.

The McRae and Worthy murders occurred eight months apart, according to the station. Like the McRaes, Worthy and his wife were wealthy. Robbery isn't a motive in either case, the station reported.

Jackson said he spoke to investigators on the Worthy case recently but isn’t convinced the two cases are connected.

"We're looking lots of places and we don't know where the investigation will take us, but we are committed to solving this crime," he said, according to WTVY.