Police searching for the suspect of a nearly 20-year-old murder now believe the killer may have been younger than first thought.
Alistair Wilson, 30, was shot on his doorstep in Nairn in the Highlands on November 28, 2004.
The murder of the bank worker still remains unsolved 17 years later.
Following a recent review of witness accounts, further analysis of timings from the night in question, and investigative developments, officers from Police Scotland's Major Investigation Team have now revised the description of the man they want to trace.
Previous appeals described the gunman as being aged between 30 and 40 years old, however, detectives now believe the man who shot Alistair may have been younger and could have been aged between 20 and 40 years old at the time.
Detective Superintendent Graeme Mackie, who is leading the investigation, said: "Over 17 years have passed since Alistair Wilson was murdered at his home in Nairn and the case continues to be reviewed and investigated by specialist officers locally, nationally and internationally.
"I am now able to issue a new appeal in relation to the description of the murderer based on reviews of witness accounts and further investigative work.
"In previous appeals, the murderer seen on the night in 2004 had been described as a man aged between 30 and 40 years of age.
"Having now carried out extensive inquires and reviewed previous descriptions and witnesses' evidence, I believe that this age range is too narrow and it is more accurate to describe the male who we believe killed Alistair was aged between 20 and 40 years old at the time.
"He was approximately 5ft 7in in height and was seen to be wearing a baseball cap and jacket.
"This would mean that Alistair's killer is now potentially aged in their mid to late 30s to almost 60 years old.
"We remain committed to ensuring the person responsible for Alistair's murder is brought to justice so that we can give his family the answers they deserve."
Mr Wilson was shot at about 7pm on Sunday, November 28 2004, after a man called at the family's home on Crescent Road, Nairn, spoke to his wife, Veronica, who had answered the door, and asked for her husband by name.
The 30-year-old father went downstairs to speak to the man and was handed a blue envelope with the word "Paul" on it.
He went inside briefly and then returned to the door for a second time where he was fatally shot.
Mr Wilson died later that evening in hospital.
The gun was recovered from a drain near his home 10 days after his murder.
Detective Superintendent Mackie said: "Someone out there knows what happened to Alistair and I hope this appeal today serves as a vital reminder that it is never too late to come forward with information.
"Do not assume that the police already know the information you possess."
Anyone who believes they can assist police is asked to contact 101 quoting incident 515 of March 4 2022 and Operation Sorn or email the dedicated inbox at SCDHOLMESAberdeen@scotland.pnn.police.uk
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