Jakarta, May 7 (IANS): A volcano erupted in Indonesia's North Sumatra province on Tuesday, spewing a dark ash cloud about 2,000 metres in height, above the crater.

The Mount Sinabung eruption lasted 42 minutes and the ash led to an orange aviation alert, the second highest after red and which warns of potential flight risks in the area, said Sutopo Purwo Nugroho, spokesperson for the National Board for Disaster Management.

Images released by Nugroho showed the dark cloud moving in a southwest direction towards villages that have been covered by a white layer of ash, Efe news reported.

Sinabung is currently the only volcano in Indonesia on the highest level of eruption alert.

Authorities have established a security radius of between 3 and 7 km from the crater and have evacuated thousands of people from the danger zone.

The eruption was not accompanied by any incandescent material, but Nugroho warned residents of lava flows.

The intermittent eruptions of the 2,460-metre Sinabung killed 16 people in 2014 and seven in 2016, although they have never exceeded grade 2 on a scale of 8 in the Volcanic Explosivity Index.

The Indonesian archipelago sits within the Pacific Ring of Fire, an area of high seismic activity with 127 active volcanoes, which experiences thousands of tremors a year.