Police and the fire service are attending a partial building collapse at a construction site in central Hamilton.
The historic Railway building on the corner of Victoria and Ward streets was already being demolished. It's believed part of a wall and a section of the roof have caved in unexpectedly.
No one is believed to have been hurt.
Radio host Mark Bunting of The Breeze, based on Ward St, says it appears to have been caused by a strong wind gust.
"It's a very windy day down here in the Waikato… apparently the wind caught a wall, blew it out, blew it back in, and it's landed inwards on the building that they're pulling down already," he told Newshub.
"It's a bit of a mess inside."
The footpath around the building was already blocked off so there was no danger to the public.
The Railway building in Hamilton's CBD (Rob Murphy)
The busy corner is currently blocked off, as is north-going traffic on Victoria St.
The 132-year-old Railway building has long been considered an earthquake risk, but only began to be pulled down recently following its purchase by Tainui Group Holdings.
Worksafe is investigating the incident.