Updated with new injury count, death toll, missing persons.
A powerful explosion ripped through an optical equipment factory outside Moscow, triggering a “total evacuation” from all nearby buildings, local authorities said Wednesday.
Plumes of smoke billowed high into the air from the Zagorsk Optical-Mechanical Plant in the town of Sergiyev Posad, around 70 kilometers northeast of Moscow, as shown in multiple videos shared on social media.
At least 30 people were hospitalized with injuries, six of whom are in intensive care, Moscow region Governor Andrei Vorobyov said, adding that another 26 people sought medical care but did not need to be hospitalized.
State media reported 56 people had sought medical attention, as of Wednesday evening.
One of the victims has died as a result of their injuries, the state-run TASS news agency reported.
Twelve people remained unaccounted for 24 hours after the deadly blast, the Moscow region branch of Russia’s Emergency Situations Ministry told Interfax on Thursday.
Sergiyev Posad’s administration ordered a “total evacuation” of all plant buildings and workshops, according to its statement.
“There are a lot of buildings that had windows blown out,” it said on the messaging app Telegram.
The cause of the blast is believed to be “workflow violations” contrary to some reports of a possible drone strike, according to emergency services cited by RIA Novosti.
Russia’s Investigative Committee, which probes major crimes, said it has opened a criminal case on the “violation of industrial safety requirements for hazardous production facilities.”
The Zagorsk Optical-Mechanical Plant, referred to as “ZOMZ,” produces night vision devices and binoculars for the Russian military as part of Russia’s defense conglomerate Rostec.
The Moscow region’s prosecutor’s office later confirmed that an explosives warehouse located next to the plant was at the epicenter of Wednesday’s explosion.
State media identified the warehouse as belonging to the fireworks supplier “Piro Ross,” which has received several warnings of safety violations in recent years and has been undergoing a bankruptcy procedure since April.
Piro Ross director Sergei Chankayev denied the official version that the detonation occurred in his warehouse, claiming instead that the epicenter was a neighboring metal pipe storage house.