Update 9am: Traffic is back to normal after an earlier crash.
Earlier: Emergency services are attending to an accident on Appin Road at Gilead after reports of a head-on crash.
It's affecting traffic in both directions.
Members of the public called Triple Zero around 7:25am to report multiple vehicles were involved in the accident in the northbound lanes, near the Belltrees dog kennels.
A stop/slow is in operation with heavy traffic conditions.
A NSW Police spokeswoman said one driver is conscious and breathing though still in the car, while another driver was being assessed by paramedics.
She said there were no life threatening injuries.