A Glasgow gangland enforcer who wrote books about his underworld experiences has died at the age of 62.

Paul Ferris is believed to have died on Tuesday night at the city’s Queen Elizabeth University Hospital after a short illness.

He was cleared of the murder of crime boss Arthur Thompson’s son, Arthur Thompson Jnr, in 1992, before being jailed for seven years in 1998 for gun-running.

His first book, The Ferris Conspiracy, was published in 2001.

It was later made into a 2013 film, The Wee Man, featuring Line of Duty star Martin Compston as Ferris.

Photographer Brian Anderson, who first met Ferris for a newspaper assignment in 2002, broke the news of his death on his Naked City Facebook page.

Describing Ferris as a best-selling author and a “former notorious criminal”, he wrote: “News of his death will come as a shock to many who knew him throughout the different chapters of his life.”

Anderson later told BBC Scotland News: “We got on really well. I found him polite, funny and kind.

“It was a shock to everyone that I remained friends with Paul for 25 years.”

Thompson, who had links to the Krays in London, was an old school Glasgow criminal known as The Godfather.

By the early 80s, Ferris had became part of his gang as an enforcer, someone who threatened and, when necessary, meted out violence. He rapidly built a fearsome reputation that extended beyond the city.

But their relationship took a remarkable twist in August 1991 when Arthur “Fat Boy” Thompson Jnr, was shot dead outside the family’s Provanmill home.

It was named The Ponderosa after the ranch in the hit US Western television series, Bonanza.

Ferris was arrested as the prime suspect in Thompson Jnr’s murder but two others were also incriminated.

His friends Joe “Bananas” Hanlon and Bobby Glover did not live to stand trial.

On the day of Thompson Jnr’s funeral both men were found shot dead in a car on the cortege route.

The murders remain unsolved.

The following year Ferris’s trial became, at the time, the longest and most expensive criminal case in Scottish legal history.

More than 300 witnesses gave evidence during the 54-day proceedings, which were estimated to have cost £4m.

The prosecution case relied heavily on the evidence of Dennis Woodman, who claimed Ferris had confessed to the killing while both men were being held in Barlinnie Prison.

Defence lawyers challenged the credibility of the evidence and argued the case against Ferris was deeply flawed.

After more than 24 hours of deliberations, the jury acquitted Ferris of murder and all other charges in 1992.

No-one has ever been convicted of Thompson Jnr’s killing.

Ferris went on to publish a number of books with writer Reg McKay, who died in 2012.