The netball club rooms at Standring Park in Wairoa were on fire this afternoon.
The Fire Service were notified at about 12:30pm and two crews from Wairoa attended.
A Fire Service spokesman said by the time crews arrived the building was "well-involved".
"Hoses were used to extinguish the blaze and firefighters left the scene at about 2pm."
He said the fire was being treated as suspicious and an investigation was underway.
