A man set himself and his car, filled with gas bottles, alight and drove it into Merrylands police station carpark at around 7pm last night.
The 61-year-old Czech national was known to police, who say he suffered from mental health issues.
He is not believed to have any known links to a terrorist organisation.
Police officers put out the flames and rescued the man from the car.
He was taken to Royal North Shore Hospital and is in a serious condition.
Police say it was a “miracle” no one else was injured in the incident.
Assistant NSW Police commissioner Denis Clifford said there is nothing to indicate the incident was related to terrorism, but it was a concern and police were “keeping an open mind”.
“Its very concerning, this is a serious incident. The police reacted very bravely and its just a miracle that no one else was seriously injured,” he said.
An police investigation is now underway. Officers from Rescue and Bomb Disposal Unit are examining the vehicle.
Memorial Avenue in Merrylands remains closed off to the public.
Business Insider Emails & Alerts
Site highlights each day to your inbox.