A man has been arrested after a serious incident at Dr Rudi's Rooftop bar in the early hours of Sunday morning.

Police arrested a 25-year-old man this afternoon.

He will be facing a number of firearms-related charges and is due to appear in the Auckland District Court tomorrow.

A gun was fired at the bar at Auckland's Viaduct on Sunday, reportedly after people who were asked to leave the bar became annoyed.

Police said at the time, there were plenty of people around and it was extremely lucky nobody was hurt in the 2.45am incident.