Detectives investigating the death of a Warwickshire teenager are keen to trace an anonymous caller who rang the incident room following a television appeal for information earlier this week.
Warwickshire Police want a man who told officers he had spoken to the person responsible for Jack Macleod's death to contact them again.
The 17-year-old, also known as Jack Fisher, from Leamington Spa, vanished after a night out in early December. His body was pulled from the River Leam by police on January 3, following a high-profile search.
A reconstruction of his dis-appearance was featured on the BBC Crimewatch programme on Tuesday evening.
The anonymous caller rang the incident room at 10.50 the same night.
Detective Inspector Bob Bradbury said: "A person has rung in anonymously stating that they have spoken to the person responsible for Jack's death and we would urge them to contact us again.
"It is possible that this is some sort of crank call but it is also just as possible that this could be genuine."