A woman, whose son disappeared 10 years ago, has made an official complaint against the police for not acting fast enough when she reported him missing.
Damien Nettles was last seen in November 1996
Valerie Nettles said officers were "too slow off the mark" in searching for her son Damien, 16, who was last seen in Cowes, Isle of Wight, in November 1996.
Hampshire police said an investigation had begun after Ms Nettles took her case to the IPCC in November last year.
A spokesman added that the search for Damien remained active.
The Independent Police Complaints Commission (IPCC) said Hampshire Constabulary was carrying out the investigation into Ms Nettle's complaint, in line with standard procedure.
Ms Nettles, who now lives in the USA, told BBC News she felt the police were "tired" of searching for Damien.
She said: "I think they're sick of hearing about it. They go through the motions because they have to and I just think they would rather it all went away."
She added: "It's been a long time before I made the complaint...I didn't want them to lose interest in the case."
Hampshire police have made a fresh appeal for help in finding Damien, to coincide with the tenth anniversary of his disappearance.
Det Supt Dave Williams said: "Damien's disappearance continues to be actively investigated, and we respond to information from the public and, in particular, from people living on the Isle of Wight.
The last possible sighting of Damien was minutes from his home
"This case is undergoing an internal review to ensure that all possible lines of inquiry have been identified and pursued.
"This remains a missing person investigation, rather than a homicide inquiry."
Ms Nettles said she had not given up hope of somebody coming forward with information about the case.
She told BBC News: "I truly believe the answer lies on the Isle of Wight, that somebody somewhere knows something, and one of these days...eventually somebody is going to come out of the woodwork."
Damien Nettles disappeared after a night out in East Cowes.