A 19-year-old woman has been sexually assaulted while on a run through a park in western Sydney.
Police say the teen was running through Duncan Park at Seven Hills at about 10am on Friday when she stopped at a bridge.
A man, armed with a knife, then allegedly grabbed her from behind and sexually assaulted her before fleeing.
The woman was taken to Westmead Hospital.
Police are now looking for a bearded man of Caucasian appearance.
He was last seen wearing light blue denim jeans, black work boots and a cap.
Anyone who has information is urged to contact Crime Stoppers on 1800 333 000 or Blacktown Police.
