Russia's Bezymyanny volcano has begun to erupt for the first time since 2012.
The volcano, located in Russia's Far Eastern region of Kamchatka, threw five clouds of ash more than 8 kilometers high on Thursday afternoon local time, according to experts from the Russian Academy of Sciences.
Scientists predict that the ash plumes could reach up to 15 kilometers above sea level, the Interfax news agency reported Thursday.
The ash is not currently affecting local settlements, but a red warning has been issued to aircraft, said Olga Girina, the head of Kamchatka's Volcanic Eruption Response Team (KVERT).
She told Interfax that scientists have been expecting the volcano to erupt since November 2016, when researchers began to spot increased volcanic activity.
Towering at a height of 2,882 meters, the Bezymyanny (Nameless) volcano is one of the most active in the world. It last erupted on Sept. 1, 2012, releasing plumes of ash which reached a height of 12 km above sea level.