Two men were shot dead at a property in Omanawa, south of Tauranga, on Tuesday.
On Thursday night, police shot dead a man in a car which was being sought in relation to the double homicide.
The driver leaned out of the window of the car and fired 20 shots at police, who then returned fire.
On Friday, police arrested a 25 year-old Auckland man in Christchurch and charged him with the two murders in Omanawa. He appeared in court in Christchurch this morning.
McGregor said no one else was being sought in relation to the woman's death.
He also said that while the series of incidents involved gang members, they appeared to be unrelated to broader gang conflict in the region.