Shortly after midnight on Saturday, police say an officer came under fire from a gunman with a military-style semi-automatic weapon in the Waikato.
The police officer gave chase to a vehicle they caught speeding in Morrinsville, before being fired on and withdrawing himself immediately.
Two other officers attended the scene on Kuranui Rd as back-up, and engaged in an intense firefight with the offender.
Waikato police District Commander Superintendent Bruce Bird said they have apprehended two occupants of the car, but are still seeking the driver, who they believe is the gunman.
The police officers suffered no injuries, but it is unsure whether or not the gunman is injured. He may also still be armed.
Supt Bird said the armed offenders squad is out in force, searching addresses for the man responsible for the attack he described as like no other he has seen.
"This is quite frightening. It's an attack of an intensity on a police officer that I have not come across in the 40 years of my service."
Police are urging anyone with information to come forward.