The brother of a man found murdered in his home in Carrickfergus last year has appealed to the public to help "break the silence".
Martin Quinn made his remarks as part of a BBC NI Spotlight programme about his brother's unsolved murder, and the paramilitary gang believed to be responsible.
Glenn Quinn was terminally ill from a blood condition when he moved into a flat in the town just weeks before Christmas 2019.
The 47-year-old had no connections to any crime or paramilitary gang but was threatened after he privately made a throwaway remark when he criticised an attack by the South East Antrim Ulster Defence Association (UDA) on a friend's business.
The South East Antrim UDA is one of Northern Ireland's largest paramilitary gangs.
According to a recent MI5-police intelligence assessment shared with Spotlight, the gang "has access to arms" and is "heavily involved in drugs supply, community coercion, intimidation and other criminality".
In December 2019, Glenn Quinn was first assaulted and threatened after he parked his car outside his flat.
Fearful for his safety, he told his brother Martin what had happened to him.
"The window was down, and the guy approached from the rear of the car, put his hand in through the window and shoved Glenn back and basically grabbed him by the throat," he said.
"He was really concerned because at the end of that assault, he was told that the UDA were coming back to sort him out."
Glenn told his brother, and others, the name of the man who assaulted him.
Security and loyalist sources have confirmed to Spotlight that person is known to them as a member of South East Antrim UDA.
Just days later, the threat against Glenn Quinn was borne out.
"Glenn had just walked into the hallway of the block of apartments and as Glenn was opening the door, he was attacked from behind.
"There were three people, and these three people, then, gave him a terrible beating.
"They went at him with weapons. He just tried to get into a ball and protect himself as best he could."
Martin is aware of some of the details of the attack because his brother managed to ring him in the minutes afterwards.
However, Martin was not fully aware of the critical nature of Glenn's injuries.
"He was quite lucid and by no means did I think that Glenn had been assaulted as badly as he had been.
"The next was Glenn couldn't be contacted and that's when Glenn's body was found.
"I still blame myself that I didn't act, didn't phone an ambulance.
"I wish I'd spoke longer to him, I wish I'd have said so many other things and if I had knew this was the last conversation I was going to have with Glenn. Tell him how much I loved him... talk about old times, and I didn't have that opportunity."
History of the UDA
The Ulster Defence Association, formed in 1971, had tens of thousands of members at its peak.
It killed hundreds of people during the Troubles in Northern Ireland and often claimed responsibility for sectarian murders using the cover name the Ulster Freedom Fighters (UFF).
The UDA had remained a legal organisation until it was banned in August 1992.
Notorious attacks by the UFF included the shooting dead of five Catholics at a Belfast bookmakers in 1992 and the Greysteel massacre the following year.
Read more here: Loyalist paramilitary groups 'have 12,500 members'
Glenn Quinn was beaten to death for passing a remark about the South East Antrim UDA.
When his family appealed for help with the PSNI investigation, they were also threatened by the South East Antrim UDA.
"I personally have been threatened three times, my mother's been threatened... They're threatening to shoot a 76-year-old woman.
"And that's part and parcel of how this organisation operate, they try to put people in fear."
Glenn Quinn's death shocked Carrickfergus and beyond, but many locals remain too scared to speak out.
The murder, they say, is what happens when a ruthless criminal gang is effectively out-of-control and perceives itself to be above the law.
"I want people to search their hearts," said Martin.
"Because, next time, and there will be a next time, it might be their brother, it might be their son, and I'd ask them to do something to stop this.
"To break the silence. And help us."
Watch the full Spotlight story on iPlayer.