State Highway 1 at Bulls has reopened after emergency services cleared the scene of a truck crash that killed a 37-year-old man this morning.

The Dannevirke man died on the scene after his truck and trailer unit smashed into the Bulls RSA at about 3.30am, causing major damage to the building.

No other vehicles were involved.

Police senior constable Chris Craig said it appeared the truck, heading south, failed to take a slight bend before the crash.

Emergency services staff used a tow truck to delicately remove the crashed vehicle from the building without causing more damage.

Bulls chief fire officer Brian Carter said the callout was a difficult one.

"‘It was a bit of a mission to get him out because of the way the truck had moulded into the building."

Carter said the truck was carrying pressurised cylinders, which was of concern initially.

"‘If those valves had snapped off then we would have had all hell to pay.

"We just made sure they [the cylinders] were secure. There were a couple that had fallen over so we just removed them from the vehicle."

Carter said removing the truck was also tricky because there was a risk that "the building would follow it".

One lane of State Highway 1 was opened after the truck had been removed from the scene as emergency services continued the cleanup.

The second lane was reopened at about 9.30am after debris from the building had been cleared from the road.

Contractors are still at the scene securing the building and the footpath is closed to the public.

- © Fairfax NZ News