Criminal contractors who prepare cars for violent offences are in police sights, days after an alleged murder plot at a daycare centre was foiled.

In an escalation of Sydney's increasingly brazen gangland wars, NSW Police on Tuesday pounced on a group of men driving through Revesby in Sydney's southwest with balaclavas and pistols.

The trio were accused of trying to intercept and kill their target as he picked up a child at a daycare centre.

While announcing new arrests, police on Friday revealed they had covertly been watching contract criminals and their network of staged vehicles or "kill cars" across Sydney for some time.

A second trio were arrested on Thursday over their alleged involvement in the G7 crew, one of several groups of contract criminals using the staged cars.

NSW Pol

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