Investigators first believed Doris Worrell was killed in a botched robbery after her husband found her fatally shot at the South Georgia business they ran in 2006.

When suspicion later turned toward Worrell’s husband, he fled the US to live in Costa Rica with the couple’s live-in nanny.

Nearly 19 years later, Jon Worrell was jailed on murder charges Thursday in rural Coffee County, where the sheriff said authorities never gave up on the cold case.

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They got a big break in April, when investigators travelled to Costa Rica and found the nanny willing to talk after her relationship with Worrell had ended.

Worrell was arrested last month at his home in Missouri, north of Kansas City.

He waived extradition to Georgia and arrived at the Coffee County jail days later.

“This case was never forgotten,” Sheriff Fred Cole told reporters at a news conference.

“And while the road has been long and often frustrating, we never gave up. Justice delayed is still justice.”

Doris Worrell had worked as a teacher and an interior designer before deciding to stay at home to raise three children.

She and her husband operated a recreation business, Jon’s Sports Park, in the small community of Douglas, about 130 miles (209km) southwest of Savannah.

Worrell called police from the business on September 20, 2006, saying he had returned from running errands to find his wife’s body.

“Many believed he was a grieving husband and his wife was the victim of a robbery gone wrong,” Jason Seacrist, an agent with the Georgia Bureau of Investigation, told reporters.

Theories about Doris Worrell’s killing evolved as investigators gathered more evidence.

In 2008, two employees of the sports park were charged with being conspirators to her murder, but the case was dropped for lack of evidence.

Meanwhile, investigators learnt that Worrell had been having an affair with the nanny at the time of his wife’s death, Seacrist said.

“Jon was concerned that if he divorced Doris, he would lose his children,” Seacrist said.

“And it’s those thoughts that led him to begin recruiting someone to murder his wife.”

He said Worrell fled to Costa Rica, where he and the nanny spent years living together while raising the Worrells’ children.

Then investigators learnt the relationship had ended and Worrell had returned to the US.

Georgia agents and sheriff’s investigators travelled to Costa Rica in April and met with the nanny, the sheriff said.

He said information she provided corroborated other evidence that authorities had been collecting for years.

Doris Worrell’s sister, LeAnn Tuggle, thanked investigators for their persistence.

She recalled her sister as a gifted artist and loving mother who had agreed to let the nanny live at her home because the young woman had nowhere else to stay.

“Sometimes she was too kind for her own good,” Tuggle said.

“Her being kind is ultimately what caused her death.”

Authorities are still trying to determine who shot Doris Worrell.

One of the men charged 17 years ago in the killing and later released has died, Seacrist said, while the other recently got out of prison in an unrelated case.

The nanny has not been charged.

“In our mind, she is not a suspect,” Seacrist said.