Up to 34 firefighters are battling a blaze in Motueka.
Emergency services were called to large two storey commercial building on High Street just after four this morning.
Seven appliances and water tankers are in attendance, and an area manager from Nelson is on route.
Ambulance staff are treating one firefighter suffering heat exhaustion.
State Highway 60 in Motueka is closed between the intersections with Greenwood Street and Tudor Street.
Motorists are being asked to avoid the area if possible