Detectives have interviewed a convicted paedophile over the disappearance of two young boys near Birmingham on Boxing Day 10 years ago.
It is thought the boys were last seen begging for food
David Spencer, who was 13, and Patrick Warren, then 11, went missing from their homes in Chelmsley Wood in 1996.
West Midlands Police have spoken to Brian Field, 70, who was jailed for life in 2001 for the rape and murder of Roy Tutill, 14, over 30 years earlier.
Field denies any involvement in the two boys' disappearance, police said.
Field, who was living near Chelmsley Wood at the time, was interviewed under caution at a police station in the West Midlands last week.
Misadventure or accident
Det Ch Supt Gordon Fraser, head of crime at West Midlands Police, said: "He remains in the inquiry and will possibly be spoken to again.
"Field can only ever be truly eliminated or otherwise once we have established what happened to the boys."
Brian Field was convicted of Surrey school boy Roy Tutill's murder
Police are working on other lines of inquiry including people who may currently be on the sex offenders' register and those with convictions for sex offences in the 1990s.
The possibility of misadventure or accident has not been discounted.
Another part of the investigation revolves around the sudden death and apparent suicide of a 15-year-old boy whose body was found close to Chelmsley Wood in 1997.
This is because of where it happened and because the boy was known to Field at the time, Det Ch Supt Fraser said.
The boys were seen on Boxing Day by a police officer with a group of friends playing on Meriden Lake, which was frozen.
He warned them of the dangers of playing on ice and told them to go home.
Patrick's bike, a Christmas present, was found near a petrol station
They then went home and told David's family they were staying at Patrick's brother's house.
The last sighting of them was at the Shell petrol station in Chelmsley Wood, just after midnight, where they were given a pack of biscuits by the assistant.
They were reported missing in the early hours of the next day.
Later, Patrick's red Apollo bike, a Christmas present, was found hidden among bins at the back of the station.
Det Ch Supt Fraser added: "Since the day they were reported missing, West Midlands Police has regularly asked for the boys, or anyone with any information about their whereabouts, or anyone who knows what has happened to them to come forward."
At least 10,000 leaflets, appealing for information, have been produced and will be distributed across Chelmsley Wood and Solihull during the weekend.
Roy Tutill was abducted, raped and strangled in 1968 as he hitch-hiked to his Surrey home from school, to save his bus fare for a new bike.