The shooter had initially tried to gain entry into a home in Auburn, near Sydney Olympic Park, before firing a shot into the residence about 10pm on Tuesday.
No one was injured, and the man fled before officers arrived, NSW Police said on Wednesday.
A forensics team was at the Auburn house early this morning after someone shot out the front window. (Bianca De Marchi/AAP PHOTOS)
As investigations began, officers were called to another Auburn street three kilometres away after a man was shot in the neck while sitting in his car.
The victim, 55, had been confronted and shot by an unknown man.
The injured man was taken to hospital in a stable condition.
During a search of the area, police found the body of a man in Duck River.
A gun was also located at the scene.
"While the investigation is ongoing, the man's death isn't being treated as suspicious," police said.
"There is no ongoing risk to the public."
Each shooting is believed to be linked.
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