A senior police officer has revealed how the family of a missing young man had been stuck in a "living nightmare" since his disappearance on Halloween last year.

Shaun Ritchie, 21, vanished while on a night out with five friends in a wooded area near farmland in the Strichen area of Aberdeenshire.

His mother Carol Ann Roy watched him leave home with a group of young men in a van but he did not return to his house the following day.

Police launched a major investigation after he was reported missing two days later and it has turned into one of the biggest search operations ever carried out in Scottish police history.

But no sign of the young man has yet been found. Only a top, belt and his trainers were recovered from an area of marshland where he was last seen on the night he vanished.

Now police have renewed their appeal for help to track Mr Ritchie down to bring closure to his family on the first anniversary of his disappearance.

Yesterday Detective Chief Inspector Matt Mackay said: "The investigation remains open. Clearly we are still actively looking to find Shaun and try to bring that closure for the family.

"Shaun's family have experienced a living nightmare since his disappearance and we all want to bring closure to the family.

"Our support to them continues alongside our efforts to find Shaun although our thoughts are with them on this difficult day.

"The inquiry remains live. We remain as committed as we have been since the start to try and find Shaun."

DCI Mackay said extensive searches of the area, which covers 21 square kilometres, have been carried out and were continuing on an intelligence-led basis.

Hundreds of officers have been involved in the complex operation wading through difficult marsh terrain trying to find the missing man since he disappeared.

Some of the ditches had to be searched again during the summer months when the water levels had receded.

However, Shaun's mother, Carol Ann Roy, said she has been left frustrated with the police investigation and is adamant that her son disappeared as a result of foul play.

The emotional Fraserburgh mother said she also feels let down by Police Scotland.

She said: "The way they have treated me is downright disgusting. I've had no liaison officer - all they kept telling me was to go to the doctors and get anti-depressants.

"They told me recently that I need to accept the fact that my son is gone and I will never get him back the way I want him.

"As a mum, how do you deal with that?

"I just want somebody to listen to me, he is my son."

Officers are now waiting on a report from Scotland's national search advisor which is based on a review of police findings and is expected to be complete in the next few days.

Yesterday DCI Mackay said he would leave no stone unturned during the investigation and insisted that police had been supporting the family.

He said: "I absolutely respect the family's views and understand their frustrations.

"I keep an open mind and the possibility of criminality is to the forefront of my mind. However, the evidential facts are that there is nothing that has been covered to date to suggest that Shaun has been the victim of any crime.

"It is an extensive inquiry which has involved hundreds of resources being deployed on the ground, dozens of detectives and so many statements being noted and productions seized.

"We would urge anybody either who has never been in contact with the inquiry team before and who has and thinks they may have something else to offer, to lift the phone and do that. All the information will be looked at and welcomed by the inquiry team."