Rare footage shows a blastwave racing out from an explosion at a Russian ammunitions depot during a series of blasts that prompted authorities to declare a 12.5-mile evacuation zone after a fire ignited powder munitions, according to local reports.
News agency Tass reported that the fire started at the storage facility for powder charges at the military unit in Siberia in the Achinsky District on Aug. 6.
According to a BBC report, the munitions depot contained tens of thousands of artillery shells.
The Russian Ministry of Defence said in a statement on Aug. 6 cited by Tass, “The fire at an ammunition depot of the Central Military District in the Krasnoyarsk Region’s Achinsky District has been fully extinguished. Powder charges stopped detonating after 05:00 Moscow time.”
— Roustem Adagamov (@adagamov) August 5, 2019
Video footage shared with social media shows an explosion at the site, recorded by a camera estimated to be about two miles away.
The normally-invisible blast wave can be seen arcing through the low-lying cloud cover, and then in the formation of condensation created by the squeezing of the air molecules in the pressure wave.
То, что осталось от посёлка Каменка в Ачинском районе Красноярского края после взрывов на армейских складах с боеприпасами pic.twitter.com/zMg33CeImI
— Roustem Adagamov (@adagamov) August 6, 2019
Some journalists on Twitter said that the timing of the sound of the explosion in the video can be used to calculate the distance and hence the speed of the blast wave, noting that it tallied with the claims made by the news reports.
“The blast wave is moving faster than the speed of sound (767mph) which is why the image of the wave passes the camera before you hear the bang,” wrote David Videcette in a Twitter post accompanying a video of the blast.
Tass news agency claims a fire in a storage unit for artillery charges has caused a series of explosion near the city of Achinsk.
Shock waves are normally invisible but the cloud cover has captured its movement. pic.twitter.com/dMNRcocKlV
— David Videcette (@DavidVidecette) August 5, 2019
“Nerd level: The men with the camera are about two miles from blast, based on sound wave. This means the shock wave is travelling at over 1080mph (1580ft/second – 447m/second). Smokeless gun powder burns at a rate of 171–631 m/s.”
Other photographs and videos show a huge orange and black fireball mushroom up from the horizon, while a shower of yellow munitions fans out like a firework.
Authorities have started evacuation from settlements within a 20-kilometer zone from the epicenter of the blasts, according to Tass.
Officials at the nearby city of Achinsk, which has a population of just over 100,000 people, said that they had been monitoring radiation levels hourly since the explosion, but that no excessively harmful substances had been registered. Gamma-ray radiation had remained at regular natural background levels, said city officials in a statement.
According to a BBC report, 14 people were reported injured, with one fatality. However, other reports, such as quote officials as denying that any fatalities occurred.
The ammunitions depot is near Russia’s biggest processing plant for alumina, the raw ore that is smelted into aluminum. Production at the plant, which is owned by Rusal, was shut down due to the explosion, reported Reuters.