Police are investigating following an armed robbery in Brookvale yesterday.

Just after 2.30pm (Thursday 4 January 2018), a man entered a financial institution on Pittwater Road, armed with a knife.

The man threatened an employee, demanding money before fleeing with a sum of cash.

Officers from the Northern Beaches Local Area Command established a crime scene and have commenced investigations assisted by officers from the State Crime Command’s Robbery and Serious Crime Squad.

As inquiries continue, police wish to speak to a man who they believe can assist them with their inquiries.

The man is described as being of Caucasian appearance, about 40 years old, 180cm-185cm tall, and of a large muscular build.

He was last seen wearing a long sleeved brown t-shirt, white shorts, and white shoes.

The employee was not physical injured during the robbery.