A second man has been found with a gunshot wound in Sydney's inner west, metres from where another man was found bleeding to death on a footpath just hours earlier.
A police operation is underway in Lewisham, as detectives try to track down the perpetrator of the attacks.
Emergency services were called to an address in the inner west suburb about 1pm on Friday after neighbours found a man with a serious wound to his chest.
Police initially said the man had been stabbed, but a spokeswoman told AAP they now believed the man was shot.
"(I'd) just came back from coffee with a friend and found him on the side of the footpath," witness Keith Mulhall told Seven News.
The man, believed to be in his 30s, died on the way to hospital.
Paramedics are now treating a second man in his 50s, found in a Victoria Street house with a serious gunshot wound to his head.
Earlier on Friday afternoon police told reporters they were working to identify the original victim and track down his killer.
Armed police and a police dog have since surrounded a property on Henry Street, where the victim was found.
Vision taken near the Lewisham crime scene showed a woman with forensic bags over her hands being led to a police car.
A police spokesman told AAP the situation was developing, and he could not confirm if the woman was a person of interest.
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