A vast cloud of ash spewing from a Chilean volcano disrupted air travel on Wednesday across much of South America, as heavy rains around the eruption site prompted fears of mudslides.
Air traffic was sharply curtailed on the continent as the ash cloud drifted over Argentina, and into
Brazil. Flights in and out of the Argentine capital Buenos Aires, a key regional hub, were canceled for most of the day.
Officials at Uruguay's main Carrasco airport however said on late Tuesday the situation was expected to normalise in the coming day, after more than 90% of flights were cancelled due to safety concerns over the cloud.
Rain mixed with volcanic ash poured down on communities near the Puyehue volcano on Tuesday, raising fears that the weight of falling water and volcanic materials could cause mudslides and threaten dams in the area, some 870 kilometres (540 miles) south of the capital Santiago.
A milky coating of ash settled on the waters of Gol Gol river, which was swollen by heavy rains.
"We are concerned about water that can drag the volcanic material certain places and cause some dams to fall," public works minister Hernan de Soliminhac said.
Enrique Valdivieso, director of Chile's National Service of Geology and Mines (Sernageomin), said heavy rains would not quell the power of the volcano but could bring gases and ash to the surface, contaminating nearby rivers.
Valdivieso said that Puyehue's eruptions have slowed but there is still a risk of large amounts of sediment pouring down from the eruption.