Blasts at the Copahue volcano, which sits in the Andes  Mountains straddling the border, began last week but because of  bad weather, Wednesday was the first day officials could fly  over it, Alberto Maturana, national director of Chile"s National  Emergency Office (Onemi), told Reuters.  

The flight over it showed bursts occurring every one to four  minutes, sending ash and gases 1,500 feet (500 meters) into the  air and dispersing the matter 30-40 miles (50-60 km) to the  north-northwest, he said. No evacuations are necessary for the  moment, he said.  

The Chilean side of the volcano, which showed similar  activity in 1992, is located in the Bio Bio region, he said,  adding that a ski resort and dams are nearby.  

About 1,800 volcanoes line the Argentine-Chilean border, of  which 28 are active, Maturana said. These 28 represent about 20  percent of the planet"s active volcanoes, he said