The menacing drumbeat of child abductions, mostly of young African-American boys, shook a city that was emerging at the time as a progressive black mecca. Gripped by fear, anxiety and helplessness, parents refused to let their children play outside. Some took their children out of school. Psychics arrived to help. The city imposed a curfew.

In 1982, Wayne Williams was convicted of killing two adults. Police suspected that he was also responsible for most of the child murders, as well as the killings of four young adults. Even though prosecutors introduced evidence to potentially link him to some of the other murders, Mr. Williams, who is serving two life sentences, was never tried or convicted of killing any of the children — no one was. But after Mr. Williams was sent to prison, 22 of the unsolved child murder cases were closed, raising an enduring question: Who killed Atlanta’s children?

Some parents argue that the city, eager to quiet the blistering headlines, yielded to political pressure and closed the books after Mr. Williams’s trial as a matter of convenience. The abrupt, unsatisfying end led to questions, doubts, anger and rumors. Through it all, the parents, gutted and grief stricken, have been searching for answers. Mayor Keisha Lance Bottoms was an elementary school student when the killing spree began, and she vividly remembers the relentless warnings against going outside alone. Last month, she ordered the cold cases reopened and the evidence retested using the most recent DNA technology. Ms. Bottoms said she hopes the new investigation will “help bring some peace to the families who for so long have felt like they were forgotten.”

Wayne Williams is now 60 years old. He sits in a state prison about three hours south of Atlanta and has steadfastly denied that he is a killer. But Erika Shields, Atlanta’s police chief, said the new investigation is not about him.

“This is about being able to look these families in the eye,” she said, “and say we did everything we could possibly do to bring closure to your case.”

‘My God. My God.’
In the summer of 1979, the remains of two teenage boys were found in the woods in southwest Atlanta. They had been missing for several days. One reportedly vanished from a skating rink. The other while returning from a movie.

“Nobody had any idea of what this was going to morph into that Saturday afternoon, that these were the first two victims of a serial killer who would murder over a span of two years,” said Danny Agan, a retired Atlanta homicide detective who investigated three of the cases on the list.

Over the next 22 months, 22 more children — including two girls — were kidnapped and strangled, shot, stabbed or bludgeoned, along with four young adults. One boy, Darron Glass, last seen in September 1980 when he was 10, is still missing.

“Every day, every night, it seemed like they were finding bodies. The city was turned upside down. There was this big dark cloud over us,” said Sheila Baltazar, 61, whose stepson, Patrick Baltazar, 12, was killed in 1981. “And we were just trying to hold on to our babies.”

Police scrambled to find any connection among the bodies that were being discovered almost routinely. At the height of the killing, more than 100 agents were assigned to the investigation as part of a law enforcement task force.

Nineteen children were already missing or killed by the time that Curtis Walker, a seventh grader, walked into his home one afternoon in the winter of 1981. His mother, Catherine Leach, was cooking when she turned to Curtis and forbade him from going outside. “Stay inside,” she said. “They’re snatching children.”

Curtis, 13, left anyway, headed to make extra money by carrying groceries for seniors. He never returned home. For two weeks, Ms. Leach, now 70, waited for news about Curtis, the second oldest of her four boys, the one who had promised to score big in Hollywood, maybe as an illustrator because he drew animals so well.

Then came a call from a neighbor: Turn on the news.

“My God. My God,” Ms. Leach cried, reliving that moment 38 years ago. “I looked at him being pulled out the water on television. I just knew that was him.”

Though her son’s killing was one of 10 considered a “pattern case” that authorities directly connected to Mr. Williams, Ms. Leach does not believe he is the killer. She is not alone. Several parents or relatives have said they believe the Ku Klux Klan was responsible.

“We want to know who killed our children,” Ms. Leach said, adding that it felt like her son and the other children had been forgotten. “That’s the answer we didn’t get.”

It was a stakeout in May 1981, near the Chattahoochee River, that led the police to Mr. Williams. Investigators eventually linked hairs and carpet fibers on the bodies of some of the victims to those in his house and car, they said.