Police have charged a man after the quick thinking of a security guard and two off-duty police officers at Sunnybank this morning.

Police will allege a man entered the loading bay at the rear of a shopping complex on Mains Road at Sunnybank just before 9.30am. He was dressed suspiciously, wearing a long black wig, a surgical mask and carrying a duffel bag.

A uniformed security officer noticed the man and began to follow him before he fled through the centre car park and along Carnaby Street. He then crossed Carnaby Street at the intersection with Leadenhall Street and entered the front yard of a residence. The man stood behind a rainwater tank and began removing his clothes.

Two off duty police officers observed the man running across the street and approached him behind the rainwater tank. The officers identified themselves and restrained the man before calling for urgent assistance.

Upon the arrival of additional crews the man was found to be in possession of a semi-automatic handgun, ammunition and other items yet to be identified.

The 52-year-old Victorian man has been charged with attempted armed robbery, possess weapon, contravene direction and unlawful possession of weapons.

He is scheduled to appear in the Holland Park Magistrates Court tomorrow.