A volcano on Indonesia’s Sumatra island has erupted, sending a torrent of searing gas more than four kilometres down its slopes.

Mount Sinabung also sent a plume of thick ash five kilometres into the atmosphere during the latest activity, said Sutopo Nugroho, spokesman for the national disaster management agency.

There were no casualties, he added.

The regional volcanic ash advisory centre in Darwin issued a “red notice” to airlines.

The 2,460-metre volcano has erupted intermittently since late 2013, displacing thousands of people.

Sinabung’s alert level has been kept at its highest since June 2015.

Mount Agung on the resort island of Bali has also been active for months, but its exclusion zone was reduced from 10 kilometres in November to 4km earlier this month after a lull.

Indonesia sits on the Pacific Ring of Fire, an area known for seismic upheavals and volcanic eruptions. The country is home to about 130 active volcanoes.