Police were called to Welch Avenue in Greenacre on December 28 to investigate reports of gunfire heard in the area.
There, officers found evidence of shots having been fired at a car, as well as empty bullet casings and damage to a fence.
Detectives believe three bullets were fired at a Mazda 3 – which had a four-month-old baby inside at the time – during an alleged illegal transaction.
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The gunman is believed to have fled the scene in a black Toyota Camry, before getting into a grey Hyundai Veloster on Highview Street and travelling toward Bankstown.
Police are searching for two females and four males who are suspected to have been involved in the alleged illegal transaction, and who may be linked to organised crime networks.
Detectives are now appealing for anyone who may have information or dashcam vision that could assist investigators to come forward.