Chile's Calbuco volcano still smoldering

Local television images showing a thick plume of smoke and ash signaled the reappearance of Chile's Calbuco volcano on Wednesday, after more than four decades of relative calm. Chile has the second biggest chain of volcanoes in the world, with Calbuco considered one of its most dangerous. The eruption could be seen in other towns up to 50 kilometers (31 miles) away.

The 2,003-meter (6,571-foot) tall volcano is situated around 1,000 kilometers south of the Chilean capital, Santiago, near the cities of Puerto Varas and Puerto Montt. The country's National Mining and Geology Service issued a high alert, restricting access to the surrounding area. Authorities said the eruption caught them by surprise, with Calbuco not being under any special form of observation.

Several hours later Calbuco erupted for a second time, with volcanic lightning clearly visible against the ash cloud. Experts believe the phenomenon is caused by the emission of large amounts of volcanic material charged with static electricity. Panic spread in the wake of the twin eruptions, with people rushing to stock up on gas and food supplies.

Some people have been allowed to return to the area to check on property and animals for short periods of time, but officials continue to watch for signs of more eruptions. Authorities have warned of the possibility of snow and ice melting on the mountain-top, which could lead to floods and a sudden surge in river water levels. There is also the danger of fast-moving mudflows.

Soldiers have been sent to help clear ash from towns and roads near Calbuco, but authorities have warned that predicted rainfalls could cause the layer of ash to harden in place. Residents have also been told to wear masks or handkerchiefs to avoid breathing in the volcanic dust. The accumulation of ash in some areas has caused roofs to collapse, with the cloud spreading across parts of Argentina.

Residents within a 20-kilometer zone have been ordered to leave by Chile's National Emergency Service. More than 6,000 people have been evacuated. The town of Ensenada, sitting at the foot of the volcano, has been all but abandoned by its 1,500 inhabitants. The government has promised financial help to those living near the volcano, who rely on revenue from the agriculture and tourism industries.