Man arrested after three-hour standoff with police in Adelaide CBD

A tense standoff between a man and police in the Adelaide CBD has been resolved peacefully. 

Elite STAR officers and police negotiators were called to Carrington Street earlier this afternoon, amid reports an armed man was holed up inside a unit.

A cordon was established to hold back onlookers and media, as police attempted to negotiate with the man. 

Officers eventually entered the building with guns drawn, and the man was later wheeled from the building on a stretcher.

He was taken to hospital and remains in police custody.

Earlier, workers evacuated from nearby offices told 9NEWS police had informed them an armed man was holed up inside.