Porirua firefighters suspect arsonists set a fire that destroyed an empty house in the grounds of Porirua Hospital.
Porirua senior station officer Boyd Atkinson said firefighters were called to the fire just after midnight on Saturday and it took five hours to put out.
The house has now been bulldozed and police are investigating.
A Capital & Coast District Health Board spokesman said the house had been occupied but the tenants moved out a week ago.
The land had been sold last year and was with the Office of Treaty Settlements, which takes control on June 30.
-The Dominion Post