Trainspotting 2 actor Bradley Welsh had been allegedly warned by police that his life was 'in danger' weeks before he was shot at point-blank range outside his home.
The 48-year-old father was fatally wounded by an assassin who dressed as a jogger outside his flat in Edinburgh at around 8pm on Wednesday.
The assailant pulled a sawn-off shotgun or similar weapon from under his jacket before firing.
Mr Welsh died at the scene despite paramedic's effort to save him.
His partner and eight-year-old daughter were in the house at the time when it took place, said Detective Superintendent Allan Burton.
The former charity worker received an 'Osman letter' from Police Scotland a few weeks ago, warning him that they believed there was a serious threat to his life.
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Police believed the murder of Welsh was a warning to notorious gangster and cocaine kingpin Mark Richardson for his role in organised crime gang which flooded Scotland with guns and drugs.
A police source said: "Bradley was a known friend of Richardson’s and while he stayed away from the criminality involved, it could be his association with Richardson and other criminal connections has cost him his life.
"One of Richardson’s other friends was attacked in his own home with machetes just recently. It could be his friends are being picked off one by one.
"Bradley was warned by police his safety was under threat and to take his security seriously."
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Police were called at around 8pm on Wednesday after multiple reports of a gunshot.
A neighbour who heard the gunshot, found Mr Welsh fatally wounded outside his flat but it was only once police arrived that his family learned of his "horrific death".
It's understood witnesses have told police the suspect was black.
However, one eyewitness told Daily Record they thought the shooter may have been wearing make-up for an 'Asian appearance' and disguise his identity.
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The former boxer, who owned a successful boxing club in the capital, turned his life around after spending his teenage years involved in gangs and protection rackets and serving a jail term.
Welsh devoted his time to charity after reforming from his football hooligan days.
He first found fame appearing in Danny Dyer’s Deadliest Men series in 2008 and then played a gangland boss in T2 Trainspotting in 2017.
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He was also involved with charity Helping Hands, which fights inequality and spent much of his time encouraging youngsters to stay away from crime by becoming involved in sport.
Thousands of tributes have been paid to Welsh on social media by shocked friends, family and regulars to his
Holyrood Boxing Gym.
Actor and TV presenter Dyer tweeted: “So sad to hear the news about Bradley Welsh. A good soul with a massive heart. A massive loss. Rest in Peace my old son.”
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Builder Morgan Currie, 20, visited the scene of the shooting and said: "I knew him through his charity work.
"He was a gentleman every time I saw him, no matter what and with anybody.
"He just kept his head down, looking after his kids and his fiance. He's a family man and just loved doing his charity work.
Cody McManus, a young man from Edinburgh, left a tribute at the gym along with a photograph of himself with Welsh.
