A critical incident investigation is underway after a man was shot dead after he pointed a gun at officers at a northern NSW police station.

The 48-year-old attended Tenterfield Police Station just before 6pm last night when he allegedly threatened officers with the gun.

He was then shot, and despite desperate attempts by responding police and paramedics, the man died at the scene.

A critical incident team is now investigating the circumstances surrounding the incident, including the discharge of a police firearm.

That investigation will be subject to independent review.

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