The family of a Beith-born banker who was murdered on his doorstep 19 years ago have made an official complaint about the handling of the police investigation.

Dad-of-two Alistair Wilson was shot dead in Nairn on the evening of November 28, 2004. He later died in hospital and the crime remains unsolved.

The BBC reported on Tuesday that Mr Wilson's family have now made a complaint to police about how they handled the investigation.

Police Scotland and the Crown and Procurator Fiscal Service (COPFS) said they had met Mr Wilson's family to discuss the matters raised by them.

A Police Scotland spokesperson said: “The investigation into the murder of Alistair Wilson remains ongoing and we are committed to conducting a full and thorough inquiry that will hopefully provide much needed answers to Alistair’s family.

“We continue to update them on our progress and they have asked that their privacy is respected at this time."

The spokesperson urged anyone with information about Mr Wilson's murder to contact the inquiry team via the telephone number 101 or email operationsorn@scotland.police.uk.

Alistair attended Beith Primary and later Garnock Academy in Kilbirnie.

After school he went to study accountancy and business law at Stirling University, and later he found himself a graduate position at the Bank of Scotland.

He was sent to work in Fort William where he met and married German-born Veronica, a graphic designer.

Ardrossan and Saltcoats Herald: Alistair with his family

Alistair and his Veronica had been bathing their two young sons when the killer knocked on the door.

A blue envelope, with the name Paul on it, was handed to Mr Wilson on the doorstep.

He went inside and showed it to his wife, but the envelope had nothing inside. When Mr Wilson returned to the door he was shot.

No one has been charged with Alistair's murder despite cold case reviews and police interviewing thousands of people.

Last year, Police Scotland said a dispute over decking at the Havelock Hotel, across the road from the Wilsons' home, was the most likely motive for the shooting.

In June this year, it emerged that a potential suspect had been jailed for an unrelated offence.

The Crown Office and Procurator Fiscas Service (COFPS) told the BBC today that the killing was "terrible crime" and its thoughts remained with Mr Wilson's family.

A spokesman said: “COPFS and Police Scotland have met with the family to discuss the matters raised by them in relation to the ongoing investigation.

“We appreciate the importance of this work to the family and they will continue to be informed, where appropriate, of significant developments.”