The Shiveluch volcano in Russia erupted on the far eastern Kamchatka peninsula on Tuesday, shooting a vast cloud of ash as high as 20 km into the sky that covered villages in grey volcanic dust and triggered a warning for flights.

The Shiveluch volcano erupted just after midnight reaching a crescendo about six hours later, spewing out an ash cloud over an area of 108,000 square kilometres, according to the Kamchatka Branch of the Russian Academy of Sciences’ Geophysical Survey.

Lava flows tumbled from the volcano, melting snow and prompting a warning of mud flows along a nearby highway while villages were carpeted in drifts of grey ash as deep as 8.5 centimetres, the deepest in 60 years, according to a Reuters report.

Pictures showed the cloud billowing swiftly over the forests and rivers of the far east and of villages covered in ash.

“The ash reached 20 kilometres high, the ash cloud moved westwards and there was a very strong fall of ash on nearby villages,” said Danila Chebrov, director of the Kamchatka branch of the Geophysical Survey.

About 300,000 people live on Russia’s vast Kamchatka peninsula, which juts into the Pacific Ocean northeast of Japan.

There were no immediate reports of casualties, though scientists said the volcano was still erupting 15 hours after the start of the eruption.

The Kamchatka Volcanic Eruption Response Team (KVERT) issued a red notice for aviation, saying “ongoing activity could affect international and low-flying aircraft.”

Some schools on the peninsula, about 6,800 km east of Moscow, were closed and residents ordered to stay indoors, head of the Ust-Kamchatsky municipal region Oleg Bondarenko said in a Telegram post.