Local officials in Russia say that an explosion at an optical factory in the town of Sergiev Posad, about 70 kilometers from Moscow, on August 9 injured at least 43 people.
Six of the injured are in intensive care with severe burns or head injuries, according to the Telegram account of the city administration. Some of the 43 people admitted to the regional hospital have shrapnel injuries, according to the statement.
The independent Telegram channel Baza shared images of a tall cloud of smoke and identified the location as the Zagorje Optical-Mechanical Factory, which manufactures night vision devices and other optical devices for the military.
Russian officials later confirmed the location.
Russian news agency TASS quoted emergency services as rejecting claims on social media that a drone attack was the cause of the explosion.
That speculation has been fueled by months of remote attacks in Russia that Moscow blames on Kiev, along with Russian reports that it "prevented" two new drone attacks near Moscow overnight.
TASS said that the explosion occurred where the pyrotechnic devices were located and that a warehouse of 1.600 square meters was destroyed.
The evacuation of all buildings and workshops in the area is underway, according to the announcement.
An inexplicable fire damaged the same factory in Zagorsk in June 2022.
Russian officials have repeatedly dismissed credible reports of attacks that damaged military or other targets inside Russia since President Vladimir Putin ordered a full-scale invasion of Ukraine in February 2022.
They described such attacks as a "red line" in the ongoing war, marking a dramatic escalation of the conflict that began with the secret invasion of Crimea in 2014.
Ukrainian officials have generally avoided publicly confirming any role in suspected drone or other operations that strike across those countries' internationally recognized borders.
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