Police investigating the murder of Bangor woman Lisa Dorrian have appealed to boat owners in the Ards peninsula for help in finding her body.
Lisa Dorrian's body has never been found
The 25-year-old shop assistant was last seen at a party on a caravan site in Ballyhalbert, County Down, in February.
Details of the police's new line of inquiry were revealed in a fresh appeal on the BBC's Crimewatch on Thursday.
Detective Chief Inspector Mark Dornan said they believe Lisa's body may have been hidden in water.
Inspector Dornan said they wanted to hear from boat owners in the area if they suspected their vessel had been tampered with.
"Boat-owners who have either bought or sold a boat privately since the beginning of February this year until the end of May, would they please contact us," he said.
"Also in relation to boat-owners, anyone in the Ards peninsula who owns a boat or keeps a boat in the Ards peninsula, would you please contact us if you think your boat has been broken into or tampered with some time from the end of February."
A reconstruction of Lisa's last movements featured in the appeal
Police believe members of the Loyalist Volunteer Force may have been involved in her killing.
In July, Prime Minster Tony Blair pledged his support in helping to locate her body.
The reconstruction also featured interviews with Lisa's family.
Detectives said they hoped the programme would encourage witnesses to come forward and assist them with their ongoing investigation.
Last week, a man in his 20s questioned by police was later released pending further inquiries.
Lisa's family have already offered a £10,000 reward for information leading to the recovery of her body.