A man has been arrested on suspicion of murdering a six-year-old boy more than 20 years ago.
Rikki Neave was last seen leaving his home on the Welland Estate in Peterborough to go to school on 28 November, 1994.
His naked body was found in nearby woodland the following day. He had been strangled.
In June last year, Cambridgeshire Police relaunched an investigation into Rikki's murder and a team of officers and specialists have been methodically building a timeline of the schoolboy's last movements.
There was also a national TV appeal on the BBC's Crimewatch programme in November during which detectives said they wanted to talk to two teenage boys over the killing.
Rikki's mum Ruth Neave leaving her son's funeral in 1995
The police force said on Tuesday that a man in his 30s from Peterborough had been detained and is in custody.
The suspect's age means he was likely to have been a juvenile at the time of Rikki's death.
Rikki's mother, Ruth Neave, was charged with murder at the time but found not guilty by a jury.
Neave, now aged 45, admitted child neglect and cruelty and was sentenced to seven years in prison.
In recent years she has called for Cambridgeshire Police to reinvestigate the murder, saying his killer remains at large.
She told a news conference in 2014: "I loved Rikki, he was a wonderful child.
"I wasn't a perfect mother but I never hurt my children and I should never have admitted to those offences.
"I know people out there think I'm a murderer but I'm determined to prove that somebody else did this to my boy."