WELLINGTON - Ski lodges were evacuated, highways briefly shut down and one man was hurt when a volcano in New Zealand erupted unexpectedly, spewing ash and rocks into the air, officials said on Wednesday. The eruption at Mount Ruapehu, located halfway between Wellington and Auckland on New Zealand's North Island, started at 8:20 pm on Tuesday (0820 GMT) and lasted for seven minutes, GNS Science duty vulcanologist Craig Miller said.

"It was just straight out of the blue," Miller told Radio New Zealand.

No further activity was reported in the hours following the eruption but it remained unclear whether any further eruptions could occur, he added.

"It's certainly not escalating into anything bigger at this stage," he said.

A 22-year-old climber, who was not named, was hurt when rocks crashed through the roof of a mountainside hut where he was staying, pinning him to the floor. He was evacuated by helicopter early Wednesday, officials said.

The eruption also briefly forced the suspension of train service along the main line in the area and the evacuation of several ski lodges in the popular resort area.

Two trails of volcanic ash and water from Mount Ruapehu's crater lake flowed down the sides of the mountain, but no significant damage was reported. (CNA/PAB)