A powerful explosion ripped through a warehouse outside the Russian capital on Wednesday, officials said, injuring dozens and sending up a massive plume of smoke visible for miles.

Local officials said the epicenter of the blast was at a warehouse storing fireworks located on the grounds of the Zagorsk Optical-Mechanical Plant in the town of Sergiyev Posad, less than 50 miles from Moscow.

The explosion raised eyebrows among some in Ukraine: The plant is a leading developer and manufacturer of optical and optoelectronic devices for law enforcement agencies, industry and health care, according to the Russian state news agency Tass. It produces night vision devices and binoculars for the Russian military as part of the country’s defense conglomerate Rostec, according to the Moscow Times newspaper.

There was no immediate suggestion of foul play, and the Russian authorities told Tass that the blast was unrelated to the reports of drones flying near Moscow overnight.

Russia’s Federal Investigative Committee said in a statement on the messaging app Telegram that it was looking into the possible “violation of industrial safety requirements.”

“We are looking into the causes of the blast,” Dmitry Akulov, the head of the district, wrote on Telegram. At least 45 people had been injured, some seriously, he added in a separate post. The authorities ordered a “total evacuation” of all plant buildings and workshops.