WELLINGTON - The New Zealand ski resort towns of Queenstown and Wanaka were shaken by a magnitude 5.8 earthquake Monday.

No injuries have yet been reported after the quake, which struck at 2:29 pm, with its center 30 km northwest of the tourist town of Wanaka in the South Island, and at a depth of 4 km.

The government's GeoNet earthquake monitoring agency rated the quake's intensity as severe.

Initially the quake was measured as 6.0 magnitude at a depth of 5 km.

Two moderate aftershocks, the first of magnitude 3.5 and another of 3.4, struck in the same area within two hours of the quake.

GeoNet data center manager Kevin Fenaughty said the quake was felt all over the bottom half of the South Island, with reports of strong shaking coming from the southern cities of Dunedin and Invercargill too.

"The most likely prognosis is that there will be a number of smaller aftershocks less than magnitude 5, continuing to decrease in size and frequency over the coming days," Fenaughty said in a statement.

The Queenstown Lakes District Council (QLDC), which encompasses an area including both Queenstown and Wanaka, said it had received no reports of injuries or significant damage.

Council chief executive Adam Feeley said a small number of windows had been broken outside Wanaka and a road had been closed due to a rockfall and a crack in the surface.

"Preliminary assessments show that all QLDC's critical infrastructure is operating normally. We have begun a more detailed inspection of our water and wastewater assets and the roads, as well as the public buildings," Feely said in a statement.

"We have also been in touch with major tourist operators and the reports so far are that there are no issues."