The Qld Police Union says it’s doing all it can to support officers who opened fire in self defence, killing a gunman in Brisbane.

Officers had no choice but to shoot a gunman after a lengthy stand-off in Brisbane, the Queensland Police Union says.

Police spent almost four hours negotiating with the man, who was armed with a handgun and refused to get out of a car that was parked at an Inala unit block on Monday.

Officers shot dead the 42-year-old when he threatened police.

Reports that he’d pointed his weapon at officers are expected to form part of an investigation by the ethical standards command. A report is also being prepared for the coroner.

Queensland Police Union president Ian Leavers said the officers appeared to have no choice and were acting in self defence.

“That is the difficult and dangerous nature of police work. Things happen so quickly. You have to make instantaneous decisions, there are no other options,” he told ABC radio.

He said the officers involved would be having a difficult time, and the union would support them, including through the ethical standards investigation.

“I can say when you’ve used force, and things have changed dramatically, you never get over it. You have to learn to live with it and it is not easy.”

Mr Leavers said the officers involved would receive ongoing counselling and legal support.

“These events, regardless of what the outcome is, are very traumatic for everyone involved,” he told AAP.

He didn’t want to comment on assertions from criminal lawyer Bill Potts that police had been provoked into engaging in “suicide by cops”.

“It’s too hard for me to comment on that issue … it is what it is, and that will be determined by the coroner,” Mr Leavers said.

“I have full confidence in the police.”

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