Two men were arrested for drug driving as police continued their Operation Moonshot operation.
The men were stopped in Wroxham Road and in Sprowston Road on Thursday (July 11) afternoon.
Police said they tested positive for cocaine and cannabis, respectively.
Another driver had his car seized after they were stopped in the Penn Grove area.
Police said the vehicle had not had an MOT since November 2017 and the driver had no insurance.
They tweeted: "He has had the opportunity to rectify these offences, but has chosen not to. Reported and vehicle seized."
Operation Moonshot, first launched three years ago in west Norfolk, uses automated number plate recognition (ANPR) cameras to detect uninsured, untaxed or unroadworthy vehicles, as well as those suspected of being linked to organised crime.
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