A gunman shot by Christchurch police last night was on the run after allegedly firing on officers just days earlier.
The shooter remains in hospital under police guard today after being shot in the lower body.
Superintendent John Price told media this afternoon that the shooting was still being investigated.
Police had tried to pull the car over last night but the driver fled.
The driver had later tried to run over an officer laying road spikes, Price said.
The man then got out of the vehicle and fired at police several times. Officers returned fire and struck the gunman. They then provided first aid to the man, Price said.
It's understood that the man had been hiding out after reportedly firing at a police car during an early morning pursuit on Saturday.
Police signalled for the man to stop on Anzac Drive, in the eastern suburb of Wainoni, just before 1am.
But he took off and aimed a gun at the police car.
"Officers saw what they believed to be shots fired through a window of the car, towards the police car," said Superintendent Lane Todd, Canterbury Metro Commander.
"Police immediately abandoned the pursuit."
Last night's drama unfolded after the shotgun-wielding man failed to stop for police on Breezes Rd about 7.20pm.
His dark grey Holden car was spiked and came to a stop on Eveleyn Couzins Ave in Richmond.
Onlookers then witnessed a terrifying gun battle between the man and chasing police officers.
"The man presented a firearm, believed to be a shotgun, and fired at police," Price said.
"Police returned fire and the offender was shot in the lower body."
Police immediately issued first aid and the man was transported to Christchurch Hospital with serious injuries. This morning police said he remained in a serious condition.
Price said police staff involved in the incident are receiving support.
"Our police staff come to work every day to ensure the safety of the public and no officer should ever be put in this position," he said.
People at a community meeting in Richmond last night were so terrified when gunshots rang out nearby that they went into lockdown - locking doors and hiding under desks.
Meanwhile, a shaken father sheltered his daughter as shrapnel flew past them during the dramatic incident.
The offender involved in the shooting in Christchurch last night is said to have allegedly opened fire at police "confidently" and without hesitation.
Witness Cathy Allden was attending the community meeting at Avebury House, off Eveleyn Couzins Ave, when the building went into lockdown.
"The first thing we heard was all the sirens getting closer and closer.
"Then we saw [a car] come up onto the pavement and all the police cars behind," Allden said.
"The next minute, the driver gets out of his car, comes around the front near the passenger side - with an automatic gun in his hand, and he just started to open fire.
"You could just hear the gun going off and then the return fire."
Allden said everyone at the meeting went into "earthquake mode" - locked all the doors and hid under desks.
"We literally put Avebury House in lockdown," she said.
"Then we saw that they had him pinned to the ground and it had all settled down."
Allden described the offender as confident and intent.
"He wasn't scared. He confidently got out of that car, went around the front and opened fire.
"He wasn't nervous and seemed quite intent in what he was doing and how he was doing it. He didn't hesitate or have to think about it."
She believes that police were justified in returning fire.
"Without a shadow of a doubt," she said.
"It was definitely the gunman that acted first, and whatever they did was the right thing to do. I don't have a scrap of anything that would say otherwise."
Along the road, Vaughan McLean was in the lounge with his daughter when he heard the sirens.
"I looked out the window and saw them chasing the car."
He said the vehicle appeared to have lost a wheel so he and his daughter went outside to look.
"We were standing here and the guy started shooting. I'm not sure if it was bullets hitting the road or shrapnel flying clean past us so we ran in and lay on the lawn behind the hedge.
"I'm lying on my daughter. There was a total of about 10 shots. Then it stopped so we went inside. About 10 minutes later we came back out and apparently he's been shot by police."
A photograph taken by Mathew Roberts from his balcony on Eveleyn Couzins Ave shows police working on the badly injured man in the street after the shootout.
The vehicle appears to have been driven on its exposed metal wheel rims.
Roberts had been in his apartment watching television when he heard wailing sirens drawing closer.
"Popping his head out" he saw a man jumping out of a car as police vehicles pulled up close behind.
Officers then jumped out and started heading towards the man "but that's when the shooting started", Roberts said.
"I heard gunshots and ... it seemed to me there were gunshots going back and forth between police and the person the police were after.
"From what I saw there was a lot - 8 or 9 shots - [fired]."
Roberts said he didn't see the entire shootout but heard the shots because midway through he rushed to a separate balcony for a clearer view where he started filming.
By the time Roberts reached the second balcony the man was already on the ground bleeding and being cuffed by police.
The incident is the second police shooting in less than a week.
A man was fatally shot by police during a roadside shootout on Thursday after robbing a Kawerau bank.
The Mongrel Mob member was suspected to have used methamphetamine.
Police attempted to stop the man's vehicle between Kawerau and Edgecumbe but he failed to stop.
About 10.20am the vehicle stopped on State Highway 30, near the Te Teko racecourse.
Officers from the Armed Offenders Squad went forward, the offender presented a firearm at them and fired a shot. The officers returned fire, hitting the man.
First aid was administered but the man died shortly after at the scene. No police officers were injured in the confrontation.