The Fire Service says it was pure luck no one was hurt when a tornado swept through Hokitika's main business district on Sunday.
Chief Fire Officer John Collett says the tornado struck about lunchtime when hundreds of people, including tourists, were in the West Coast town's centre.
Mr Collett says the tornado covered only a 200-metre area, but caused substantial damage to some businesses and it will take a few days to complete repairs and clean up debris.
The Railway Hotel was worst-hit, with much of its roof ripped off. However, others nearby were also affected, he says.
"Another adjacent commercial building lost some very large doors - they were actually thrown up in the air about 200 metres. A large amount of iron from all the roofs and different bits and pieces were just strewn all around the town.
"It was right on lunchtime in the middle of the tourist season, so there was hundreds of people around town during time of the day, so it's fortunate no one's got hurt at all."
John Collett says it was incredible to see windows broken yet paperwork remained on desks as if nothing had happened.
