The elderly parents of a man missing for almost 30 years have been arrested on suspicion of his murder.
Steven Clark was 23 when he was last seen using toilets near Saltburn pier on 28 December 1992.
Detectives believe Mr Clark, who was left disabled from injuries in a car crash as a child, had "come to harm".
Cleveland Police said those arrested were later bailed but has not named Doris and Charles Clark, who confirmed their arrest to the Press Association.
Mrs Clark, from Marske, said the couple "absolutely" denied murdering their son.
She added: "There's nothing I can say, except for the shock of being arrested."
Mr and Mrs Clark have previously appealed for help in solving the mystery of what happened to their son.
No body has been found and cold case detectives reopened his case earlier this year.
A missing persons report said Mr Clark was last seen at 15:00 GMT after a family walk.
He went to use the gents' public toilets while his mother went into the ladies at the same time. He was not seen coming out of the toilets and did not return home.
Det Ch Insp Shaun Page said there were "many question marks" over Mr Clark's disappearance.
"As a result of our initial reinvestigation and the fact that there is no proof of life, we believe that Steven has come to harm," he said.
"I appreciate that we're asking people to think back to the 1990s, but there may be people who knew Steven and have information that may prove vital to this case."
Mr Clark had a severely damaged left arm, a damaged leg and pronounced limp with his ability to walk described as severely impaired.
Shortly before he went missing he was awarded the apprentice of the year award from the Rathbone Society in Redcar which helped people with disabilities improve their employment skills.