A leading detective has said the abduction of a Glasgow accountant a year ago has been one of the most frustrating cases he has dealt with.
Mr Ramsay was abducted by men posing as police officers
Det Supt Willie Prendergast, of Strathclyde Police, said he remained determined to solve the mystery of Andrew Ramsay's disappearance.
Mr Ramsay was handcuffed and thrown in a car by two men claiming to be police.
Officers have interviewed more than 1,000 people since the 52-year-old disappeared on 22 February 2006.
They have also taken 300 statements and pursued 1,300 lines of inquiry.
The hunt has also taken police to cities in England, Wales and Northern Ireland - as well as Belgium to visit the accountant's associates.
Mr Ramsay, who will be 53 next month, disappeared shortly after 1900 GMT.
He and his partner Beverley had left the Quo Vadis pub in Paisley Road West on the evening he disappeared, and went into the G101 Off Sales.
They then walked the short distance to his home in Berryknowes Road, Cardonald, where he was taken away.
A Honda Accord was seen travelling on Paisley Road West at Hillington Road South around that time.
Det Supt Prendergast said: "This has been one of the most frustrating inquiries I have dealt with.
"Since last February, officers have investigated over 1,300 lines of inquiry and taken more than 300 statements.
"This does not include over 1,000 people interviewed in door-to-door inquiries.
"Someone out there knows something and, for whatever reason, hasn't come forward."
The abduction has also been featured on BBC's Crimewatch programme, and a £5,000 reward for information leading to his recovery remains on offer.
Det Supt Prendergast appealed for anyone with any potential information to come forward, no matter how trivial it seemed.
He said: "I would stress to the public that they shouldn't assume what we know, but should contact the police with any little piece of information they have.
"Although this inquiry has been scaled down due to lack of information, it is still being treated as an abduction and will remain an active inquiry until it has been satisfactorily resolved."