Detectives investigating the murder of Marvin Couson who died in 2015 from brain injury 13 years after being shot outside a Shoreditch nightclub have arrested a man today for firearms offences.

East London Advertiser: Marvin... died in hospital in 2015 with brain injury from being shot 13 years before. Picture: Met PoliceMarvin... died in hospital in 2015 with brain injury from being shot 13 years before. Picture: Met Police (Image: MPS)

The 40-year-old suspect is in police custody on suspicion of possessing a firearm and with intent to endanger life.

Marvin died in August, 2015, having been confined to a hospital bed since being shot outside the Lime Bar in Curtain Road on May 12, 2002.

"It's remarkable that it's 17 years since he was shot and his killer remains at large," Marvin's sister Margaret Couson said today.

"That awful incident has ruined so many lives. Not a day goes by when we don't think of him.

East London Advertiser: Marvin Couson and his sister MargaretMarvin Couson and his sister Margaret (Image: Archant)

"Marvin loved life and his family and had the best years of his life ahead of him. His two children turn 20 and their only memory is their dad is in hospital—they have been robbed of just having their dad there."

A £40,000 reward remains on offer to anyone with information leading to the arrest of those responsible for Marvin's death.

But detectives have been facing a wall of silence over the years.

Det Chief Insp Noel McHugh said: "We are days away from the 17th anniversary of Marvin's shooting and have made a significant arrest this morning. I hope it encourages people to take themselves back to the Lime Bar in 2002.

"Some may be reluctant to get involved or perhaps just feel they've moved on as it was so long ago.

"But Marvin's family haven't been able to move on, after years of heartache visiting his hospital bedside every day for 13 years while he lay paralysed before finally succumbing to his injuries. They need help to move on."

The family is determined not to give up their fight for justice after being "in trauma for 17 years" since the night of the shooting.

Margaret Couson said today's arrest was "really encouraging". She added: "I hope it makes people talk. Yes 17 years have passed, but witnesses are living with what they saw that night.

"It's possible that the gunman didn't intend shooting Marvin and he may have turned his life around—but that doesn't take away the torturous 17 years that the family have faced."

Marvin was with a friend when a disturbance broke out between a hip-hop promoter in the bar that night and a group of 15 men.

Another man approached and fired a gun. He was later described as black, in his early 20s, wearing a distinctive black three-quarter length duffle coat with large buttons and a hood.

The shot caused security staff to clear the crowded bar with 200 customers streaming out into Curtain Road and Worship Street.

Marvin, a 26-year-old retail security systems fitter, was among those fleeing the scene.

His friend saw a red or burgundy T-reg Ford Fiesta with at least two men speeding along Curtain Road after another shot was fired.

He walked back to find Marvin on the ground outside the bar with a gunshot wound to the chest. Marvin was taken by ambulance to the Royal London Hospital in Whitechapel with injuries to his heart and other internal organs, then transferred to the Royal Hospital for Neuro-Disability in Putney.

Marvin spent the next 13 years unable to care for himself or leave his hospital bed and couldn't communicate or understand anything said to him.

He died at 10.40am on August 8, 2015, from brain injury that was a direct result of the shooting 13 years earlier, a post-mortem found.

Detectives are appealing to anyone to come forward who was in the Ford Fiesta seen speeding along Curtain Road on the night of the Lime Bar shooting.

Det Chief Insp McHugh said: "Maybe they're scared as they feel embroiled in his actions. But there was only one person who pulled that trigger that night.

"Marvin died because he got caught up in a dispute that night between organised crime gangs from London and Birmingham. He was not involved in gangs or crime, but was an innocent victim of a dispute that had nothing to do with him.

"I hope for the sake of Marvin's family and his two now grown-up children that someone will do the right thing and come forward."

Detectives are appealing to anyone with information to contact the incident room on 020-8785 8099, or Crimestoppers anonymously on 0800-555111. The Lime Bar no longer exists and is now the Queen of Hoxton pub.