A police mission to stop what was earlier deemed a "suspicious vehicle" in Greenlane had a dramatic end 43km away.
A police spokesperson said they received information about a suspicious vehicle in Greenlane this morning.
Police officers attended and attempted to stop the vehicle but it fled, they said.
It was then tracked it travelling south to Papakura, before heading back north.
The vehicle rammed a patrol car before stopping on SH1 at Orewa, police said.
The occupants of the patrol car were not injured.
One person has been arrested. Officers continue to remain at the scene.
Waka Kotahi NZTA said the northbound Johnstones Hill Tunnel was temporarily blocked following the incident.
A lane north has been reopened.
The agency is asking motorists to allow extra time through this area.
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