Two boys in Masterton have admitted lighting a fire at a landfill transfer station which destroyed more than $300,000 worth of property.
Four fire engines and more than 16 fire fighters were called to the Nursery Road buildings at 7pm on Saturday.
A single storey building, a front end loader, large quantities of cardboard and about 2000 wheelie bins were destroyed.
Police say the boys used a lighter to set the cardboard on fire.
While they have admitted responsibility for the damage, police say they could not give any reason for their behaviour.
The two boys have been referred to police youth aid. Both are aged 11.