Police are appealing for public assistance following a fatal crash in Acacia Gardens last night.
Shortly before 9.30pm emergency services were called to the intersection of Sunnyholt Road and Quakers Hill Parkway, Acacia Gardens, after a motorcyclist had reportedly lost control and crashed.
NSW Ambulance paramedics attended and treated the 21-year-old male rider.
He was taken to Westmead Hospital in a critical condition, however died shortly after.
Officers from Riverstone Police Area Command established a crime scene.
As inquiries into the circumstances surrounding the incident continue, police are appealing for witnesses, including motorists with dashcam vision, to contact Riverstone Police Station or Crime Stoppers on 1800 333 000.
A report will be prepared for the information of the Coroner.