Police are reviewing security footage after a van was used in a break-and-enter at a Prospect warehouse on Monday.
About 2am, a single cab van with a flat tray parked up against a wall at the site on The Great Western Highway.
An unknown amount of people then used the tray as a means of scaling the wall to gain access to the site, which activated an alarm.
Security found the van when they arrived and approached the vehicle, finding a man inside.
The man, described as being of Pacific Islander appearance, refused requests to provide identification and quickly drove away from the scene.
Anyone with information is urged to contact Blacktown police station, 9671 9199 or Crime Stoppers, 1800 333 000.