Chile volcano Calbuco quietens but remains unstable

Men shovel ash from Calbuco volcano off a road in Ensenada, Chile 25 April 2015 — There are health concerns about the fine dust entering people's lungs

The Chilean authorities have warned of further eruptions at the Calbuco volcano in southern Chile, which erupted twice this week.

During a lull in its activity, most airports in Chile and neighbouring Argentina reopened.

They were closed because of the tons of fine volcanic ash thrown into the atmosphere.

More than 6,000 people living close to the volcano have been evacuated.

People sweep volcanic ash from the roof of a building in Puerto Varas, Chile, Sunday, April 26, 2015. — The head of the Chilean National Mining and Geology Service said the volcano's eruptions could last weeks or months

Scientists say they are also concerned that rain expected to fall in the next few days could mix with the ash to form dangerous mudslides.

Calbuco is estimated to have spewed out 210 million cubic metres (7,420m cubic feet) of ash which has coated the land for around in dust as light as flour or talcum powder.

In some towns, local TV stations showed people wearing masks clearing the heavy ash off the roofs of their houses and nearby roads.

Two sheep remain in a meadow covered with ash after the eruption of the Calbuco volcano, in the town of Ensenada, region of Los Lagos, in southern Chile, 26 April 2015. — The government aims to evacuate 4,000 sheep and 350 cattle trapped in ash-covered fields with no water.

On Saturday, the Chilean government announced it would provide aid to cover huge financial losses incurred by local farmers and to help evacuate thousands of farm animals.

International flights were delayed or cancelled because of concerns over the ash cloud created by the volcano.

The eruption on Thursday created a cloud of ash that rose 20km (12 miles) into the air.

Volcanic ash can be extremely dangerous to aircraft as the fine particles can damage engines.

Map of Argentina and Chile, showing Buenos Aires, Santiago and the Calbuco volcano

View of the Calbuco volcano from Puerto Varas, Chile on April 24, 2015. — A large column of smoke streamed from Calbuco volcano on Friday forced thousands to evacuate.

In March, the Villarrica volcano, 200km (125 miles) north of Calbuco, erupted in the early hours of the morning, spewing ash and lava into the sky.

Calbuco is located in Los Lagos, a region popular with tourists because of its mountain landscapes of volcanoes and lakes.

Chile has about 90 active volcanoes.

The country has been hit by a series of natural disasters in recent months including flooding in the usually arid north and wildfires in southern forests.