Southern Chile's Calbuco volcano has erupted for the second time in a day, after being dormant for about half a century.

The first eruption on Wednesday sent a thick plume of ash and smoke several kilometres into the sky, local television images showed.

More than 5,000 people were evacuated from the sparsely populated area about 1,000km south of the capital Santiago and near the tourist town of Puerto Varas.

A state of emergency was declared after the first eruption and a curfew was enforced overnight.

Video footage of the first eruption, which occurred at around 6pm local time (21:00 GMT), showed a spectacular mushroom-shaped cloud of ash and smoke, that turned red as the sun went down.

Chile's Interior Minister Rodrigo Penailillo gave a televised address, calling for calm. Penailillo said the military was being sent into Llanquihue province to help evacuate people and keep order.

He added that water was being sent to the area, as it was unclear how much ash may have fallen and contaminated water supplies.

Later, Penailillo said there had been no reports of deaths, missing persons or injuries. He urged residents to evacuate and warned of possible lahars, a mix of water and rock fragments that flow down a volcano's slopes and river valleys.

Wednesday's eruptions also triggered flight cancellations in Chile and Argentina.

Al Jazeera's Lucia Newman, reporting the Chilean capital Santiago said on Thursday that thousands of people across the country and in neighbouring Argentina were still stuck at airports.

"In Chile flights are not taking off to as far north as Concepcion, 630km from the volcano, as northeasterly winds blow ash in the direction of the capital."

Juan Martinez, a Chilean who was trying to return to his home in Puerto Montt, near the erupting volcano told Al Jazeera that the country was going "from one disaster to another."

Chile's Villarics volcano erupted last month, followed by an unprecedented drought, devastating forest fires and freakish floods in country's north, which home to the famed Atacama desert.

Trevor Moffat, who lives in Ensenada, about 10km from the volcano, said he and his family fled when it erupted.

"It sounded like a big tractor trailer passing by the road, rattling and shaking, guttural rumbling. ... We left everything there, grabbed my kid, my dog, got in the car with my wife," Moffat told the Reuters news agency.

Calbuco last erupted in 1972 and is considered one of the top three most potentially dangerous among Chile's 90 active volcanoes, according to the AP news agency.

Chile, on the Pacific "Rim of Fire", has the second largest chain of volcanoes in the world after Indonesia, including around 500 that are potentially active.

In March, volcano Villarrica, also in southern Chile, erupted in spectacular fashion, sending a plume of ash and lava high into the sky, but quickly subsided.