A man has been formally charged in connection with an alleged murder conspiracy in the southwestern area of Sydney.

The investigation kicked off on December 28 of the previous year when police started receiving intelligence regarding a purported plot to kill a 34-year-old man.

Authorities made a pivotal move around 4 p.m. yesterday by stopping a vehicle on Campbelltown Road in Woodbine.

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During the stop, officers arrested a 26-year-old man who was found in the car as a passenger.

Police searched the vehicle and seized mobile phones, a balaclava and black clothing.

He was taken to Campbelltown Police Station and charged with conspiring and agreeing to murder, and participation in a criminal group contributing to criminal activity.

A search warrant was executed on a home in Bloodwood Place at Bradbury about 5pm where police seized a CCTV system, prohibited drugs and additional clothing.

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All items have been taken for further examination.

The Bradbury man was refused bail and is set to face Campbelltown Local Court today.

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