WELLINGTON, July 17 (Xinhua) -- All 28 men trapped underground during a fire in a New Zealand mine Tuesday have safely returned to the surface, according to the mine company.
U.S.-owned Newmont Waihi Gold issued a statement that said a truck engine fire was reported at about 5 a.m. at the company's Trio mine near Waihi in the northeast of the North Island.
The miners followed procedure by going to three refuge chambers and reporting by phone to the surface, said the statement.
As a result of the fire, smoke was coming out of the mine's vent shaft, said the statement.
The Trio mine was a hardrock gold mine and there was no risk of an explosion, it said.
All mining operations at the mine have been halted.
Radio New Zealand reported the company's operations general manager Glen Grindlay saying that one man might have been affected by smoke, but all the others were not injured.
Mine officials said there would be a thorough investigation into the fire and the mine would not reopen until the investigation was completed.
Grindlay said they would wait for the fire to burn out before re-entering the mine.
The Department of Labour said two inspectors from a high hazard unit which was formed after the Pike River disaster which killed 29 miners in 2010, were on their way from Wellington to Waihi.