Single vehicle accident on Hawkesbury Rd near Gahnia Way on Tuesday, August 15 about 12.45pm.
A 45-year-old man has been taken to Westmead Hospital in a serious condition after an accident on Hawkesbury Rd near Gahnia Way at Winmalee.
An Ambulance NSW spokeswoman said paramedics were called to the scene just before 12.45pm on Tuesday to attend the single vehicle accident.
She said the man was trapped for a short time, and taken to Westmead Hospital by road ambulance in a serious condition with suspected head injuries.
There are significant delays on Hawkesbury Rd, with traffic affected in both directions.