A volcano has erupted in central Indonesia, prompting authorities to warn airlines about volcanic ash in the air.

Mount Soputan in North Sulawesi province spewed ash nearly 20,000ft into the sky.

The eruption status has been raised from an alert to “standby” 2.5 miles from the summit and up to four miles to the west-south-west.

A graphic showing the location of the volcano
(PA Graphics)

“Standby” status means people should avoid the area nearest the volcano and have masks available in the event of ashfall.

Planes were warned of the ash clouds because volcanic ash presents a hazard for plane engines.

Soputan is on the northern part of Sulawesi island, where a central region was severely damaged by an earthquake and tsunami on Friday.

Indonesia has dozens of active volcanoes.

Authorities are continuing to search for possible survivors (AP)

Meanwhile, the death toll from an earthquake and tsunami in Indonesia has increased to 1,407.

National disaster agency spokesman Sutopo Purwo Nugroho said 519 of the bodies had been buried.

The magnitude 7.5 earthquake and the tsunami it generated devastated the city of Palu and nearby communities in Central Sulawesi province.

President Joko “Jokowi” Widodo has visited the city and said aid is now starting to arrive.