One person has died and 35 others have been injured after a series of blasts in an arms depot in Russia.
The explosion happened in the Ulyanovsk region in central Russia.
Russia's Vesti-24 state television showed a huge fire lighting up the evening sky above the city.
The blasts were compared to a giant firework display visible 15km away.
The blast knocked out the windows of nearby houses.
The blasts took place while munitions were being detonated in a controlled operation at the city's number 31 arms depot, the Ulyanovsk branch of Russia's FSB security service said in a statement.
Russia's Defence ministry said that fire broke out when soldiers attempted to decommission munitions at Arsenal No. 31
Regional governor Sergei Morozov said that there were 40 people working in the workshop of the arms depot when the explosion occurred.
35 of the workers are currently listed as missing.
The explosions broke windowpanes and caused 'strong vibrations' in streets near the depot, a spokesman for the Ulyanovsk mayor's office
3,000 people have been moved from the surrounding area.
City police warned residents to acquire supplies of gauze masks and store drinking water.
The city of Ulyanovsk is located 893km southeast of Moscow.
It is best known as the birthplace of Bolshevik leader Vladimir Lenin.