The Associated Press

SANTA ANA, Calif. – Investigators searched for decades for the killer of an 11-year-old girl who disappeared while walking home from summer school in a case that gripped a California seaside community.

A photo of a smiling Linda O’Keefe has hung for years on the wall of the police department in Newport Beach, reminding investigators to keep pressing forward on cold cases like hers.

More than four decades later, authorities in Southern California said Wednesday that a Colorado man has been arrested and charged with killing her in 1973. The announcement came the same day authorities said they charged a man with killing an 11-year-old boy near Los Angeles in 1990.

In Linda’s case, authorities said they got a hit last month from a genealogical database that matched a DNA sample taken when her body was found strangled in a ditch a day after she went missing. Increasingly, investigators have found a powerful tool in databases made up of DNA samples submitted by people seeking to learn about their ancestry.

“The detectives dogged this case,” Orange County District Attorney Todd Spitzer told reporters, declining to say whether the suspect or his relatives submitted DNA for genealogical purposes. “We have every opportunity in the world to solve so many of these cold cases that we never had hope in the past of solving.”

James Neal, 72, was arrested in Colorado Springs, Colorado, on Tuesday and charged with murder with special circumstances, Spitzer said.

“He seemed like a good guy,” Neal’s landlord, Michael Thulson, told the Colorado Springs Gazette. “I had no indication he was capable of anything even 10 steps less than this, which just shows you what you don’t know.”

Neal’s son-in-law told the newspaper that the family was not ready to comment. It was not immediately clear if Neal had an attorney who could speak on his behalf, and the voicemail was full on a number listed for him.

Neal was due to appear in court in Colorado on Thursday.

In Los Angeles County, authorities said Edward Donell Thomas, 50, has been charged in connection with kidnapping and killing William Tillett. The boy disappeared in 1990 while walking home from school in Inglewood, and his body was found in a dark carport later that day. The coroner determined he had been suffocated.

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A combination of old evidence and “advanced technology” led to Thomas, Inglewood Police Chief Mark Fronterotta told reporters without releasing details.

Fronterotta said investigators don’t believe Thomas acted alone. He and the boy’s brother urged anyone with information to come forward.

“I just want to keep the momentum going” so the family can have closure, Hubert Tillett said.

The police chief was on the force at the time and said the case left “an indelible mark in my mind, in my heart.”

Thomas was being held without bail, and it wasn’t known if he had an attorney. His arraignment is scheduled for April 4.

In Newport Beach, O’Keefe was walking home from summer school in July 1973 when she vanished. She was last seen talking to a stranger in a van and never made it home, police Chief Jon Lewis said.

Her family and friends searched for her and called police. The next morning, her body was found.

Authorities said they never gave up the search for her killer, even after decades passed and her parents had died. The suspect’s DNA profile was uploaded to a criminal database in 2001 but there were no hits for years, authorities said.

They got a hit this year on a genealogical database, leading investigators to obtain a DNA sample from Neal, and it matched, Spitzer said.

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Neal lived in Southern California at the time of O’Keefe’s killing and moved to Florida soon afterward, where he changed his name, Spitzer said. The prosecutor declined to say whether Neal has a criminal record.

O’Keefe’s two living sisters have been told about the arrest, authorities said. Over the years, hundreds of people have worked on the case, the police chief said.

One of them was now-retired Newport Beach police Officer Stan Bressler, who said O’Keefe’s death stunned the community and was never forgotten.

“Every once in a while, you just think, ‘Gee, I wonder if we’ll ever find him,’” he said.