On 18th March 2007, a lahar (volcanic mud flow) spilled down Mount Ruapehu in New Zealand. After an eruption of the volcano in 1995, a 40m high wall of tephra had built up around the crater rim. In this latest event the wall was breached, allowing a mixture of acidic rock fragments, volcanic ash (tephra) and water to spill down the flanks of the mountain. Although there was reported to be no loss of life and no significant damage as a result of the lahar, the potential for extremely hazardous events still exists. This is demonstrated by a 1953 lahar from the same volacno which killed 151 people. The image is from NZPA/Stephen Barker/Associated Press.For a video clip of the event go to the BBC link: Volcano spews rivers of mud
