Shots have been fired at three homes in Sydney's south-west.

Police are investigating the drive-by shootings but say nobody was hurt.

They say an unknown vehicle was seen outside each home before several rounds were fired.

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The first was on Clarence Street in Merrylands at 10.45pm and the next was on nearby Lockwood Street.

The third, at 11pm, was on Monash Street in Wentworthville.

NSW Police superintendent commander Simon Glasser said all three locations were known to police for links to organised crime.

"That is a line of enquiry for us, believing these offences have been targeted," Glasser said.

Glasser said the two Merrylands properties were unoccupied at the time, while three people were inside the Wentworthville home.

Police want to speak to the driver of a white Hyundai sedan seen driving away from the Wentworthville home around the time.

"We believe at least two, possibly three, people involved were in that vehicle at the time," Glasser said.

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