It was shortly before 7pm and barman Tam Cameron had been told there were two men in the car park waiting to see him.

It's not clear even to this day whether the meeting had been pre-arranged or if the duo turned up unannounced.

What we do know is that one of the two men standing outside the Auchinairn Tavern in Bishopbriggs pulled out a gun and shot the 49-year-old through the chest, before both men fled the scene.

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Tam was found by horrified colleagues and customers and an ambulance was called.

However, he was dead on arrival at nearby Stobhill Hospital in Glasgow on June 28, 2007.

Immediately after the shooting, the pub was sealed off and police questioned people who had been drinking there at the time. Forensic teams also combed the car park for clues.

The victim had lived in Bishopbriggs with his wife Angela, 42, and daughters Lisa, 27, and Amber, 16. It then emerged that tragedy was the second to hit the family in the last two years.

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Tam and Ross

The couple lost their only son Ross after the 20-year-old was stabbed in the chest at a New Year party on Jan 1, 2006. In October that year Andrew Burns, 21, from Milton in Glasgow, who had been charged with Ross's murder, was convicted of the lesser offence of culpable homicide and jailed for nine years.

Detective Chief Inspector John McGovern, the officer leading the investigation into Tam's murder, was at pains to point out that he didn't think there was a link between the two killings.

He said at the time: "Thomas Cameron was working as a barman in the pub and went into the car park where he met two men.

"Some sort of disturbance occurred, resulting in him being shot.

"We believe he knew his killers and that he was the intended victim - however, we are still trying to establish a motive for this crime."

McGovern added: "Thomas was a family man and his wife and two daughters are naturally distraught at his untimely death.

"His son was killed 18 months ago and I am aware of the speculation connecting these deaths.

"I would stress that there is absolutely nothing to suggest that there is any connection between the killings nor any other incidents that have occurred in the area.

"This sort of behaviour is totally unacceptable and those responsible must be caught and brought to justice."

A suspect quickly emerged for the killing who police believed had fled Scotland and was now in Spain.

The then-unnamed 43-year-old man lived in the Possilpark area and a number of addresses there were searched.

At that stage, his name was not released but forces across Europe, particularly Spain, were given his description and told to look out for him.

A month later a second murder took place which appeared to have links to the murder of Tam Cameron.

The partially decomposed body of Billy Bates, 43, was found in an oil drum on July 28 by council workers during a routine cleaning and dredging operation near the Erskine Bridge in West Dunbartonshire.

He had gone missing shortly after Thomas had been murdered.

Bates, who was from Possilpark in Glasgow had also been wanted for questioning over the barman's murder, along with the suspect believed to be in Spain.

Detectives had been trying to track down Bates since Tam Cameron was murdered.

It's understood he had confided in pals that he wanted to contact them and provide a statement.

Instead, his partly decomposed corpse was found stuffed in an oil drum in the River Clyde, near the Erskine Bridge.

Police believe his body was in the water for up to two weeks and had been the victim of a "sustained attack" and suffered "horrific injuries".

Bates had not been seen for several weeks before the discovery of his body.

His family contacted police after they released a photograph of distinctive gold rings he was wearing - in a bid to identify him.

At this stage, police were still trying to establish a motive for Tam Cameron's murder.

It was rumoured that he owed money but whatever the reason nothing could excuse the brutality of the slaying.

In the next four years, the search for the prime suspect spread across Europe and further afield.

However in a dramatic development in 2011 Strathclyde Police, now Police Scotland, went public for the first time with a name and a photograph and description was issued of their suspect with the permission of the Crown Office.

He was Derek McGraw Ferguson who used a number of aliases including William Murdoch Henderson and went by the nickname Deco.

Officers believed he had been travelling between Ireland, Portugal, Holland, Turkey and Spain under an assumed name and was being financially supported.

He was described as bald, with green or blue eyes and around 5ft 2.

He also had tattoos of an arrow and heart design with a dagger, while part of his left ear was missing and had used an Irish accent in the past.

Officers from Strathclyde even traveled to Madrid to make a joint appeal for information with the Spanish authorities.

It was was part of wider crackdown on British criminal suspects living abroad codenamed Operation Captura.

Though others were arrested as a result of the investigations, Ferguson still remained at large.

In 2017 it was revealed that the suspect many have made made a secret return to Scotland in 2015 possibly on a fake passport.

But he left before officers received information about his trip home.

By this time a special team have been set up at the Scottish Crime Campus in Gartcosh, Lanarkshire, to find Ferguson.

At the time the man leading the investigation DCI Mark Bell also appealed to Ferguson to hand himself in adding: "It must be a difficult and stressful existence looking over your shoulder all the time.

Last June on the 14th anniversary of Tam Camerons murder a £5000 reward was issued by Crimestoppers.

Police also released a new photo of Fergison from the time and computer-generated images of what he may look like now.

Detective Superintendent John Wyllie, who was now leading the investigation, said:"I am continuing to appeal for anyone who has any knowledge of Ferguson's whereabouts to get in touch with any information which could help us trace him.

"Since 2007, we have carried out extensive inquiries and I am certain that the commitment and tenacity of our officers and our partner agencies will result in Ferguson being found.

"If you know Derek Ferguson or have any information which will help us locate him, please come forward.

"Any information may be of significant assistance. If you are unsure whether information you know will assist our inquiries, please just share it with us."

Over the years the hunt for Ferguson has also involved police forces across Europe, Interpol and the National Crime Agency in London Ferguson's name has appeared on numerous websites of high-profile 'wanted' criminals suspected of having committed serious crimes.

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Many of the appeal over the years have targeted Scots holidaying in Spain with Ferguson's face featuring on giants digital screens and posters outside nightclubs, bars, supermarkets and restaurants.

Leaflets in Spanish and English have been handed out to both locals and vacationers.

Police thought they had gained a breakthrough two years when they cracked an encrypted phone network.

People involved in organised crime had been used the system to discuss their activities, thinking it was secure.

But law enforcement experts infiltrated the platform and managed to read the tests sent between the crimijals.

Information shared from the huge international effort helped Police Scotland officers seize £25million of drugs and £7million of dirty cash.

But there was still no sign of Ferguson.

Over the years the police have been unrelenting in their search for the murder suspect who would now be in his late fifties.

While they have been very successful in bringing others to justice in the same time, Ferguson still eludes them.

One theory is that he is being being hidden in safe houses to avoid capture.

Given his distinctive appearance and height it seems remarkable that he has managed to elude the authorities for so long.

As the hunt for him enters its 15th year the family of murdered Tam Cameron are still waiting for justice and answers.

A Police Scotland spokesperson said: “Derek Ferguson remains at large and Police Scotland is working in partnership with our colleagues in the National Crime Agency and foreign law enforcement agencies to track him down.

"If anyone has information about his current whereabouts I would urge you to get in touch with Police Scotland on 101 or the independent charity Crimestoppers, anonymously.”