The ash cloud from the eruption of Shiveluch, one of Kamchatka’s most active volcanoes, extended over 500 kilometers (more than 300 miles) northwest and engulfed several villages in grey volcanic dust.
Officials closed the skies over the area to aircraft. Local authorities advised residents to stay indoors and shut schools in several affected communities. Two villages had their power supplies cut for a few hours until emergency crews restored them.
Ash fell on 108,000 square kilometers (41,699 square miles) of territory, according to the regional branch of the Russian Academy of Sciences Geophysical Survey. Scientists described the fallout as the biggest in nearly 60 years.
The village of Klyuchi, which is located about 50 kilometers (some 30 miles) from the volcano, was covered by an 8-centimeter (3-inch) layer of dust. Residents posted videos showing the ash cloud plunging the area into darkness.
Kamchatka Gov. Vladimir Solodov said there was no need for mass evacuation, but added that some residents who have health issues could be temporarily evacuated.
Shiveluch has two parts, the 3,283-meter (10,771-foot) Old Shiveluch, and the smaller, highly active Young Shiveluch.
The Kamchatka Peninsula, which extends into the Pacific Ocean about 6,600 kilometers (4,000 miles) east of Moscow, is one of the world’s most concentrated area of geothermal activity, with about 30 active volcanoes.