A Red Alert has been declared in the Los Lagos Region of Chile after Calbuco Volcano erupted twice in less than 24 hours.

Thousands of people within a 20 km radius of the volcano have been evacuated.

The first eruption occurred late in the evening on 22 April 2015 (local time) and lasted over an hour, leaving a 10 km ash cloud. There had been no warning of the eruption, as the volcano had been dormant for more than 50 years - when its last major eruption occurred in 1962 - and no activity had been expected. Officials were still monitoring Villarrica Volcano, which erupted in March and was considered a higher risk for further activity. Reports indicate that Calbuco only registered activity on monitoring systems less than an hour before its eruption.

The second eruption occurred seven hours later on the following morning and early reports indicate that it was on the same scale as the first eruption.

No injuries have been reported, but a state of emergency was declared after the first eruption and the town of Ensenada and other locations near the volcano have been evacuated. The nearby cities of Puerto Montt and Puerto Varas have been affected by the eruption, with Puerto Montt now blanketed in ash.

Residents outside the immediate danger zone in the region have been advised to remain indoors to avoid the hazard posed by the ash, which could cause respiratory problems. The ash is expected to cause disruption and ONEMI reports that the cloud is forecast to move in a North North East direction.

There have been reports of lava within the eruptions, leading to concerns of ice melting on the mountain, and potential flooding of rivers. A third eruption is currently considered to be likely.