Geologists say the explosions were due to the accumulation of melted snow in Ubinas’ crater.
“It's like pouring cold water on a hot plate. That will cause a reaction," said seismologist Victor Aguilar, of the University of San Agustin in Arequipa.
He said that the only threat to the area’s residents was from falling ash, which had been mainly blowing away from populated areas since the blasts.
In 2006, Ubinas belched ash, smoke and toxic gas over southeastern Peru, killing livestock and polluting water supplies.
It had previously been dormant for nearly 40 years.
Photo: Institute for Geology, Mining and Metallurgy (Peru)