Police are using abandoned, red-zoned properties in Christchurch for tactical training exercises this week.
They are warning residents in Queensbury Street, in the suburb of Burwood, they may hear gun shots or explosions briefly on Wednesday, Saturday and Sunday as part of the exercises.
Tactical commander inspector Steve Mather says the exercises will simulate the use of firearms and small explosives to gain entry into houses.
He says police have used other red-zoned locations for training before as they provide a realistic environment for staff to test their skills.
He says police are using locations where there are very few occupied homes nearby.