Vulcanologists say molten rock appears to be moving higher inside New Zealands Mt Ruapehu.

They say elevated gas output, high lake temperatures and tremors continue to indicate unrest at Ruapehu, but say it is not clear whether an eruption is imminent.

Eruptions in 1995 and 1996 wrecked the ski seasons in those years and were economically disastrous for the area, driving the Turoa ski resort into receivership.

Scientists have been monitoring the mountain closely since a moderate-sized steam eruption in the crater lake last September.

No further eruptions have occurred, but skiers were warned last month that the increase in gas output and the higher temperature of the volcano means there is ongoing activity.

The mountain is on alert level one - the highest is five - and further checks on temperature and gases will be made this week.

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