Sheila Keen-Warren was arrested and charged with first-degree murder in the 1990 death of Marlene Warren in Palm Beach County, Fla. Police say Keen-Warren was disguised as a clown when she shot Warren. (Reuters)

Just after breakfast on a warm May day in 1990, a white convertible Chrysler LeBaron pulled into Marlene Warren’s driveway in Wellington, Fla., and a clown emerged.

The clown — wearing an orange wig, with a red bulb nose and a painted-on smile — carried a bouquet of flowers and two balloons. One said: “You’re the greatest!”

The clown offered the flowers and balloons to Warren, witnesses would later recount — then pulled out a gun and shot her in the face.

As Warren crumpled to the ground, the person in the clown disguise calmly walked back to the Chrysler convertible, witnesses said — then disappeared for the next 27 years.

“This is the strangest thing I’ve seen in all my 19 years in law enforcement,” Bob Ferrell, a spokesman for the Palm Beach County Sheriff’s Office, told reporters at the time. “As she went to take the flowers and balloons, the clown shot her.”

Now, authorities say they have finally apprehended the suspected killer at the center of the bizarre cold case.

Sheila Keen Warren, 54, was arrested Tuesday at her home in the Appalachian Mountains and charged in Marlene Warren’s 1990 death.

It was unclear whether Sheila Warren had hired an attorney.

“Any murder’s horrific. It doesn’t matter whether you’re wearing a clown costume or not,” Palm Beach County Sheriff’s Sgt. Richard McAfee said after announcing the arrest.

“Taking another person’s life is a horrific incident,” he added. “It just took us 27 years to bring closure to the victim’s family. Murder cases never go away.”

Warren was in a jail cell in Abingdon, Va., near the Tennessee state line. She had waived her right to an extradition hearing, and Palm Beach County authorities have 10 days to pick her up, according to CBS affiliate WJHL.

Sheila Keen Warren, 54. (Palm Beach County Sheriff’s Office)

“I didn’t think that it would ever happen; there’s always hope, but I’d prefer to have her instead,” Marlene Warren’s mother, Shirley Twing, 87, told the Florida Sun-Sentinel after the arrest was announced. “She was a special young lady, she was a pretty young lady with long blond hair.”

“It feels good that they found [the killer], but it’s taking me back to the memory of it and it’s kind of hard,” Twing added. “I feel like crying now, but I’m glad it’s over.”

Louis Sessa, a retired detective, had been stewing over the case for nearly three decades. He told ABC News that the unsolved case still haunted him after he retired in 2006.

He’d long suspected that Sheila Keen Warren was Marlene Warren’s killer, but he could never prove it.

Investigators called him just before they made the arrest.

“Even after 27 years the case never goes away,” he said. “It was a big relief for me to hear she was in jail.”

Marlene Warren, who was 40 when she died, lived in the ritzy Wellington Aero Club in South Florida, police said.

Described as a “private aeronautical community,” it has its own landing strip and taxiways that lead to each home, so residents can “enjoy the luxury of flying right to their doorstep,” according to the Aero Club website.

Marlene Warren’s husband owned a car dealership; she managed the couple’s rental properties.

But Michael Warren had been having an affair with Sheila Keen, a then-27-year-old recent divorcée who repossessed cars for his dealership, according to the Sun-Sentinel, which covered details of the sprawling homicide investigation in 1990.

Other employees told investigators that the pair frequently took long lunches together. He had also started paying her rent, the newspaper reported at the time.

Investigators looked at both as suspects in Marlene Warren’s killing, and the circumstantial evidence piled up.

Hours after the killing, workers at a costume shop called police and said a woman had bought a clown costume two days earlier — then picked Keen out of a photo lineup, the newspaper reported in 1990. Clerks at a Publix grocery store near her home told investigators that Keen bought flowers and balloons 90 minutes before the killing.

Even so, the case went cold, because investigators didn’t have enough probable cause to make an arrest.

The inquiry did lead to legal trouble for Michael Warren. He was sentenced to prison in 1992 on 43 counts of odometer tampering, grand theft and racketeering, NBC News reported. He left South Florida after being released from prison.

In 2014, the cold case squad reopened the investigation of Marlene Warren’s death.

They hoped that advances in DNA analysis and re-interviewing key witnesses would lead to a break in the case.

And they learned a new detail about Michael Warren and Sheila Keen: They had gotten married a dozen years after Marlene Warren’s killing, and were operating a restaurant together in Tennessee.

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