The body of a murdered County Down woman may have been dumped at sea, police have said.
Police poster of Lisa and the boat that may have moved her body
Lisa Dorrian, 25, was last seen at a party on a caravan site in Ballyhalbert on 28 February 2005. Despite extensive searches her body has never been found.
Detectives said they thought the Bangor shop assistant's body may have been moved months after the murder from a hiding place on land.
Police also renewed their appeal for information over the murder.
Detective superintendent George Hamilton said the police now believed her body may have been taken out to sea some time between late June and early August last year.
"We now believe that Lisa's body was moved from an original location," he said.
"We believe this original location was on land, possibly in a building, an outhouse or a shed.
"We don't believe Lisa was originally placed in water. But we now believe Lisa's body may have been moved."
New murder appeal posters issued by the PSNI contain pictures of Lisa and a boat which they believe may have been used to transport her body.
He said his officers were anxious to find the original hiding place of the body and that even months later modern forensic science would enable them to gather information.
Ms Dorrian's family attended Wednesday's launch of the renewed appeal which came a week before the anniversary of her killing.
Lisa's little sister, Joanne, made her own emotional appeal to the public for help.
"We see her friends getting on with their lives and going out on Friday nights," she said.
"We can't ever have her back, we can't grieve because we never had the chance to say goodbye."
Detectives are asking anyone who owns outhouses or sheds on the Ards peninsula and may have been aware of suspicious activity there to contact them.
They are also appealing for members of fishing and boating communities for help in tracing the movement of a red or orange day cruiser type boat which they believe may have been used to move Lisa's body in July or August of 2005.
Her family have offered a £10,000 reward for information leading to the recovery of Lisa's body.