A major police operation is underway in the inner-west Sydney suburb of Croydon Park after a number of shots were fired.

At least one person was seen being taken away from the scene by paramedics, while another man arrived at Canterbury Hospital with gunshot wounds.

NSW Ambulance says two other people have been treated for minor injuries that did not involve a firearm.

Heavily armed officers from the Tactical Operations Unit have sealed off the area on Georges River Road and are urging motorists to stay away from the area.

Local residents are being advised to stay indoors. Loading

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