Police are investigating a series of attempted armed robberies after security guards were threatened and shots fired overnight.

Three men with firearms attended a licensed premises on Fairfield Road, Rocklea at around 1.40am on Friday morning, demanding cash.

The venue’s security guard was struck by one of the offenders before a shot was discharged into a wall.

The trio then fled the scene in a white Volkswagen Polo.

Around 2.30am, the same group attempted to rob a licensed venue on Mount Lindesay Highway, Park Ridge.

They forced entry and fired a shot into a door.

Nothing was stolen in either attempt and neither security guard required medical treatment.

The group’s vehicle was dumped in Waterford West around 3.45am. 

Police believe the two incidents are linked, and are appealing to the public for help.