Police arrested a man and seized a semi-automatic handgun after a chase in Blacktown yesterday.
Police said at about 3pm they stopped a grey Mazda hatchback on Kildare Road at Blacktown.
A 20-year-old Westmead man, who was a passenger in the back of the vehicle, ran from the car towards Blacktown train station.
As the man was trying to jump over a guard rail, he tripped and sustained lacerations.
Police said a firearm fell from a bag being carried by the man during the chase.
The man became aggressive towards paramedics and hospital staff while being treated.
On his release from hospital this morning he was taken to Blacktown police station where he was charged with possess unauthorised pistol, possess unregistered firearm, not keep firearm safe, and two counts of resisting police in the execution of their duty.
He was also charged with stalk/intimidate to cause fear or physical harm towards paramedics while he was being treated yesterday.
The man was also charged in relation to three aggravated break and enters in western Sydney earlier this month.