Two men took themselves to hospital after being shot in Westmead last night.
Just after 10.50pm, September 16, police were contacted following reports of several gun shots being heard in Priddle Street, Westmead.
A short time later, two men – both aged in their 20s – presented separately at Westmead Hospital with gun shot wounds.
Police allege both men have an association with bikie gangs.
Both received treatment, and one has since been discharged.
The second remains in hospital, but is not believed to have life-threatening injuries.
Neither man was co-operating with officers, police said, adding that, while the details were not yet clear, the shootings were believed to have been "linked to criminal activity".
Priddle Street was being examined by forensic specialists. Detectives from Holroyd Local Area Command and State Crime Command officers were due to interview the men today, police said.
Investigators said the men had links to separate outlaw motorcycle gangs. They did not specify which gangs but media reports said one of the men had links to the Hells Angels.
Both State Crime Command and local detectives are investigating the circumstances surrounding the incident, and intend to conduct further interviews with both men later today.