A MANHUNT was is under way and parts of Wallaroo on the Yorke Peninsula are in lockdown as police search for a gun-wielding man.

Officers fired a shot at the man, who was initially wanted over a high-speed pursuit, after he allegedly levelled the firearm at them earlier in the afternoon.

A heavy police presence, including STAR Group officers and the armoured Bearcat vehicle, then descended on the Copper Coast town.

media_camera A police roadblock in Wallaroo as the hunt for the suspected gunman continues. Picture: Dean Martin.

media_camera The armoured Bearcat is being used in the manhunt. Picture: Yorke Peninsula Country Times

Officers are moving from property to property within a “declared dangerous area” in the town in search of the armed man. Dozens of premises were being scoured.

Police have established a cordon around several streets and specialist STAR Group officers are using a Bearcat armoured car, which has been seen around properties.

Dog squad officers and the PolAir helicopter are assisting in the search.

It is understood police know the identity of the man and believe he is holed up in one of the properties.

Residents were either not allowed to return to their homes or were told to stay inside and lock all their doors and windows.

STAR force officers complete with armoured Bearcat arriving back at staging ground in Wallaroo after searching nearby houses for armed man. @theTiser pic.twitter.com/Fjwf5nzRJp — Mitch Mott (@MitchMottTiser) July 16, 2018

Police are trying to locate an offender with a firearm in Wallaroo. A section of the town between Cornish Terrace, East Terrace, Ryan Street and Gouge Street has been declared a dangerous area. More in tomorrow's @YPTimes. pic.twitter.com/hZPCPBiVFF — Rhiannon Koch (@RhiannonKoch) July 16, 2018

Just before 10pm STAR Group officers left Wallaroo and raided a property in nearby Kadina in what they called an “intelligence-gathering exercise”.

The residents of the house were interviewed outside on the curb as other STAR Group officers searched the property.

The residents could be heard telling police they did not know the man police are searching for.

SA Police Commissioner Grant Stevens confirmed the dangerous police operation and that a

shot had been fired.

“There have been some shots fired, I am advised,” he said. “If they (the public) are aware it is the person we are seeking we strongly advise them not to approach the person and to call police.

“No police were injured but we have yet to have a proper assessment of whether that person (the gunman) has been injured.”

Officers first spotted the man driving a Commodore sedan on the Spencer Highway and tried to pull him over just before 1am Monday.

Emergency services coming and going from a lockdown in Wallaroo which follows a man pointing a hand gun at police and officers firing a single shot back. @theTiser pic.twitter.com/K4P1kkxUJ3 — Mitch Mott (@MitchMottTiser) July 16, 2018

The driver refused and was last seen on East Tce before police stopped their pursuit.

Patrols continued to search for the car in the township but were unable to find it or the driver until just after 1pm, when it was found abandoned near the intersection of East Tce and Cornish Tce.

Officers spotted the man in nearby Daly St, where he allegedly produced a handgun and pointed it at police.

media_camera Police at the scene in Wallaroo. Picture. Dean Martin

media_camera Parts of Wallaroo remain in lockdown as police search for an armed man. Picture: Nine News

An officer fired a shot at the man, who then ran off, police said. No police were injured but remains unclear if the wanted man was injured.

The man was described as caucasian, about 160cm, 70kg, medium build, with brown eyes, light brown hair and wearing black long pants and a black windcheater.

Police warned the public he should not be approached and asked anyone who sighted him to call triple-0.