Ecuadorean authorities say 425,000 people live in areas that could be threatened by fast-moving mud and rock flows if there is a major eruption of the Cotopaxi volcano.

Top disaster official Maria del Pilar Cornejo briefed reporters Monday as bad weather scrapped a planned flyover of the snow-capped 5,897-meter (19,600-foot) volcano, which is 50 kilometers (30 miles) south of Quito.

Cotopaxi last rumbled Saturday, when it shot ash more than two miles high and spilled some lava. Four hundred people were evacuated briefly.

The volcano began showing renewed activity in April. Its last major eruption was in 1877.

President Rafael Correa decreed prior censorship Saturday on the volcano, causing consternation among press freedom groups. All media are prohibited from publishing information about Cotopaxi that doesn't come from an official source.