Police were forced to subdue a youth with a taser after he allegedly threatened an officer with a bayonet and a knife near Culverden.
North Canterbury police area commander Senior Sergeant Malcolm Johnston said police were making inquiries about a dog seen running loose on the highway some 3km east of Culverden about 9pm on Saturday when they were approached by an 18-year-old armed with a bayonet and a knife.
"He became very aggressive and refused to drop the weapons," Senior Sergeant Johnston said.
The police officer was able to get out of the patrol car and tasered the youth.
He was arrested and charged with possession of an offensive weapon and assault for allegedly waving the weapons in the officer's face.