Scientists said they were unsure whether an earthquake centered at New Zealand's Mount Ruapehu volcano caused an eruption.
The small earthquake, measuring about 2.8 on the Richter scale, occurred around 10:30 p.m. Wednesday, causing a body of water to form and break a trigger cable that is part of a volcanic warning system called a lahar, TV New Zealand reported.
While there was no lahar, scientists were unsure if there was a small eruption.
"The most likely scenario, is we've had what's called a 'blue sky eruption.' Nothing's happening, you get an eruption and then everything goes back to normal," New Zealand Geological and Nuclear Sciences spokesman Steve Sherburn told TVNZ. "Worse-case scenario is we have the start of something like the (1995 Ruapehu eruption activity)."
Other than triggering the lahar alarm, there were no reports of damage.
Copyright 2006 by United Press International
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