An investigation into the shooting death of a man on the northern NSW border is continuing as police rule out claims the incident was related to a bikie gang brawl.
The heavily-tattooed victim was dropped outside the Tweed Heads hospital on Saturday afternoon by a woman believed to be his girlfriend.
He was suffering a single gunshot wound to his torso, and was immediately treated, but died soon after.
The man, who is understood to be a father in his 30s named Ace Hall, had strong links to the Mongol bikie gang, Seven News reports.
Detective Superintendent Wayne Starling says while the man was known to police, he was not a member of a bikie group.
He also dismissed reports that the shooting could be fallout from a brawl between rival gangs outside the Seagulls Leagues Club at Tweed heads on State of Origin night.
"It had nothing to do with the brawl at the Seagulls club," Mr Starling told AAP.
"But we look at all avenues of inquiry. We don't mark off any line."
A property in an industrial area on Machinery Drive at Tweed Heads was shut down on Sunday as homicide detectives searched for clues in connection to the shooting.
Strikeforce Varnell has been established to investigate the homicide.