The fire in a McNulty Road building was extinguished at 10pm last night (Wednesday), after eight fire appliances and two support vehicles were called to the site.

More than 40 firefighters from crews based in Clyde, Cromwell, Luggate and Alexandra attended at the height of the fire.

Fire and Emergency Southern Communications shift manager Brodie Keay said crews would not be returning at this stage.

"A fire investigator is on route this morning and will be looking into the fire.

'It was a large commercial building with a fair amount of our team there last night."

Last night the Central Otago District Council let people know via a Facebook post that water supplies in Cromwell may have be affected due to the fire services demand for water.

CromTrans is at 147 McNulty Road, Cromwell and provides transport services to clients in Central Otago and Southland.

CromTrans main building remains undamaged. PHOTO: Anna Robb