Volcano alert downgraded

No evidence of a lahar has been found on Mt Ruapehu despite an eruption. Picture / Alan Gibson

A warning for climbers on Mt Ruapehu has been downgraded from "high risk" to "medium risk".

The Department of Conservation downgraded the warning for the top of the mountain yesterday after scientists found volcanic activity at the crater lake last week was minor.

Scientists inspected the lake on Saturday and determined a small eruption had occurred during an earthquake on Wednesday night but was confined to the crater basin. The earthquake triggered the mountain's lahar warning system and it was thought a lahar might have occurred.

But no evidence of one was found and GNS Science said seismic activity was now at "typical background levels". However, DOC said people still entered the crater basin at their own risk and needed to be aware of normal volcanic, climate and alpine hazards.