Russian media sources have confirmed a major fire is ongoing at Krasnoyarsk’s Machine-Building Plant (also commonly known as "Krasmash") in the Siberian city of Krasnoyarsk, Russia, after stunning images and video began appearing on social media Friday.

The Krasmash plant is known for producing some of the most advanced missiles in Russia's ballistic arsenal.

#Russia: Krasmash military plant is on fire in Krasnoyarsk. Krasmash is RS-28 Sarmat ICBM manufacturer https://t.co/eQ7lNFShHy pic.twitter.com/AHgAHzlznI — Liveuamap (@Liveuamap) April 26, 2019

The fire is reported to have first engulfed the roof of the sprawling facility, but is as yet of unknown origin. State media sources have cited local emergency authorities to say the fire is ranked at a "category four" — representing the highest emergency response and difficulty for extinguishing a fire.

Firefighters told Sputnik the blaze has "reached 5,000 square meters (54,000 square feet), and a section of the roof has collapsed.

Ballistic missile workshop on fire in Krasnoyarsk, #Russia. pic.twitter.com/Sjy7WEURHL — zana amedi (@zana_med) April 26, 2019

Video footage showed thick black smoke coming from the blaze which appears multiple blocks in width hovering over the city.

The Krasmash factory in Krasnoyarsk is reportedly on fire. Krasmash builds ballistic missiles, including the new Sarmat ICBM, and the Sineva and Layner submarine-launched ballistic missiles, as well as products for the space industry. 1/https://t.co/JcjBxqKDCi pic.twitter.com/pj2ynxBdFp — Rob Lee (@RALee85) April 26, 2019

Russian emergency authorities have sought to assure residents that missiles produced at the factory are not in danger of exploding; however there are fears over the release of potentially harmful chemicals into the air.

Early reports suggest the fire is not concentrated in a main missile production part of the sprawling campus, but in a section leased out for refrigerator storage and production.

Aerial photos of fire at KrasMash plant show the size of fire https://t.co/EF3KWRRB8B #Russia pic.twitter.com/vtsuLc94JM — Liveuamap (@Liveuamap) April 26, 2019

According to Russia's RT:

The fire occurred at a refrigerator-making factory, which is also located on the premises. A roof of a warehouse that stores ice-boxes, before they are shipped to customers, collapsed. There were reportedly 5,000 refrigerators inside.

Fire at the Krasnoyarsk Machine-Building Plant,🇷🇺#Russia.

The Krasnoyarsk Machine-Building Plant is a leading producer of submarine-launched ballistic missiles. pic.twitter.com/UxDxmr5H8R — Capt(N) (@Capt_Navy) April 26, 2019

A mobile air testing lab and environmental crews have been reported dispatched to the site as firefighters continue to battle the massive blaze.

Russian military has cordoned of the area of Krasmash plant. 9 firefighting engines and 38 firemen deployed to the site https://t.co/LbqGvneaaw #Russia pic.twitter.com/dTfwwnDlhw — Liveuamap (@Liveuamap) April 26, 2019

One heavy duty armament believed to be produced at the factory is the Sarmat heavy intercontinental ballistic missile, described previously by Defence Blog as a "liquid-fueled, MIRV-equipped, superheavy thermonuclear armed intercontinental ballistic missile" and among the Kremlin's largest rockets.

One of the missiles produced at the Krasmash facility now on fire: the Sarmat heavy intercontinental ballistic missile, via Defence Blog

The Krasmash facility also produces the Sineva ballistic missiles, among others over the almost century of the plant's existence.

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