About 6.30pm today, an 18-year-old local man was sitting in his stationary motor vehicle which was parked in a car park on King Street, NSW Police say.
The teenager told police that an unknown man suddenly entered the vehicle and sat in the passenger seat.
After producing a knife the man demanded cash from the 18-year-old.
The teenager accelerated away and after his vehicle crashed into a parked vehicle it rolled.
Police have been told the offender was then able to flee and was last seen running east on King Street.
Emergency services were contacted with Ambulance paramedics treating the 18-year-old man for minor injuries. He was later conveyed to Hawkesbury Hospital in a stable condition.
Police from Hawkesbury Local Area Command have established a crime scene at the location and are appealing for anyone who witnessed the incident to come forward.
Police are urging anyone with information in relation to this incident to call Crime Stoppers.
