About 10 homes were evacuated in a Lower Hutt suburb on Wednesday afternoon after potentially dangerous chemicals were found underneath a house.
Police, fire crews and members of the Army were called to the property in Stokes Valley.
Police say the owner of the house had recently bought the property and discovered small bottles of chemicals under the house.
He alerted emergency services when he saw that some of the chemicals had crystallised.
Two members of the bomb squad removed the bottles and they were later detonated at a nearby park.
Police say the chemicals were for use in fireworks and not drug ingredients.