A 22-year-old from Sutton has been arrested and charged with possession of a prohibited firearm, discharging a firearm in a public place, breaching a good behaviour order and breach of bail.

Police were called to the rear of a gym in Gozzard Street, Gungahlin, just after 10pm on Sunday night following reports of a fight between two groups of men.

Police saw a man from one group seemingly trying to conceal a gel-blaster firearm, closely resembling a Glock handgun.

Police say a second man in the group was found to be in possession of a large knife and will be charged via summons for possessing a knife in a public place.

Gel-blaster firearms are prohibited and, police say, significant penalties can apply if a person is found to be in possession of one.