QUITO, Ecuador — Ecuadorean authorities said Monday that up to 325,000 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 as bad weather scrapped a planned flyover of the snow-capped 5,897-meter (19,600-foot) volcano, which is 50 kilometres (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, worrying press freedom groups. All media are prohibited from publishing information about Cotopaxi that doesn’t come from an official source.

This could affect tourism into the country and potentially flights into the Quito international airport.