Hawaii County police have arrested the parents of a missing boy, Peter Kema Jr., on drug and weapons offenses after serving a search warrant at their home in connection with a welfare fraud investigation.

Officers arrested Peter J. Kema Sr., of Pahoa, at 2:25 p.m. Wednesday on suspicion of ownership of a prohibited firearm, ownership of prohibited ammunition, altering a serial number on a firearm, second-degree promotion of a detrimental drug and fourth-degree promotion of a harmful drug.

His wife, Jaylin M. Kema, was arrested Tuesday at a home on Uilani Drive in the Ainaloa subdivision in Puna on suspicion of theft.

The Hawaii Police Department was asked to assist the state Department of Human Services’ Welfare Fraud Investigation Division with the execution of a search warrant.

During the search, police also recovered items unrelated to the DHS investigation.

On Wednesday morning, while Jaylin Kema was at the cellblock, police arrested her on suspicion of ownership of a prohibited firearm, altering a serial number on a firearm, second-degree promotion of a detrimental drug and fourth-degree promotion of a harmful drug.

No charges have been filed and police are continuing their investigation in the theft, drug and firearms charges.

The 1997 disappearance of their son, a 6-year-old known as “Peter Boy,” is considered one of Hawaii’s most notorious unsolved cases.

Last year, Hawaii County Prosecutor Mitch Roth said police were interviewing people and pursuing new information in the case.

The mystery of what happened to Peter Boy, whom state records showed suffered repeated abuse in his short life, has persisted, ever since Peter Boy’s father told authorities he gave his son to a longtime family friend while on a job-hunting trip to Oahu.

Police were unable to verify the existence of Auntie Rose Makuakane, the woman who Kema said took custody of Peter Boy in the summer of 1997. Peter Boy’s mother did not report her son missing until January 1998.

Hawaii County police initially investigated Peter Boy’s disappearance as a missing-person case but changed it to a homicide investigation when they turned over the files to prosecutors in 2000.

No body was ever found, and no one was ever arrested in the case.

Peter Boy’s maternal grandfather, James Acol, said Wednesday that he has disowned his daughter and not been in contact with her. Acol said he is under a gag order on the murder case.

Regarding the welfare fraud case, Acol said the couple “never did get separated.”

“People say they were separated,” Acol said. “He was living with her all this time. They were faking they were separated.”

Peter Boy and two older siblings were removed from their home by child welfare authorities shortly after Peter Boy’s birth in 1991 because of reports of child abuse. They eventually were reunited with their parents, but reports of abuse continued to surface. When Peter Boy was 3 months old, he was hospitalized with multiple new and healing fractures in his body.

Records released in 2005 by the Department of Human Services, which investigates child abuse cases, revealed that Peter Boy’s sister told a psychologist nearly a year after her brother disappeared that she saw his dead body on two occasions.

Acol said Peter Boy’s brother, Allan Acol, now 27, and sister, Lina Acol, now 22, are living with him and doing well.

“I adopted Lina after the case with Peter Boy missing,” he said. “She is doing great. She just had a son. That’s my grandson. We’re doing great. He’s starting to crawl and walk. We’re enjoying life with him.”

Allan Acol “is doing OK,” he said, adding, “He has a job. He is doing well to survive.”

Police Maj. Sam Thomas said there have been no developments in the murder case, and it was deferred to the prosecutor’s office years ago.

“Over the years, they’ve asked for a couple of follow-ups, but it’s remained within their realm,” he said.

Roth could not be reached for comment Wednesday evening. A spokeswoman for DHS declined comment on the case.