A six month long investigation targeting online drug dealers has disrupted the line of supply in Canterbury, police say.
As part of the operation three search warrants were executed and a firearm, methamphetamine, cannabis and cash were recovered, Detective Brad Greenstreet said.
Two men and two women were arrested and the charges include dealing in Class A, B and C controlled drugs.
Mr Greenstreet said the fact that this supply network was operating online showed one way in which the drug supply was becoming more sophisticated.
He said as an organisation, the police must adapt to that.