"Something big exploded right over the plant. Luckily, no one was killed, but several workers received minor injuries and have already been treated for their wounds and cuts," Vasilyeva said in a phone interview. "Some people thought that the storage was on fire, but what many witnesses took for smoke was a cloud of zinc concentrate powder thrown up and around, resulting from the explosion impact."
Zinc concentrate is totally harmless, she said.
Dozens of witnesses shot videos and photos of the incident and posted them to the Web. The Russia-24 news channel aired dramatic images of the destruction at an indoor athletic stadium in Chelyabinsk, where at least two people were seen covered with blood among debris. No one was killed, the report said.
The country last dealt with a major meteor on Feb. 12, 1947, when the Sikhote-Alin meteor, estimated to weigh over 23 tons, exploded over the taiga in the Russian Far East. The explosion created 106 craters over 13.5 square miles of wooded area.
The Tungusska event in June 1908 struck an uninhabited wooded area in central Siberia. Scientists still argue about what the object was but the force of its explosion was estimated to be between 40 and 50 megatons -- more powerful than a hydrogen bomb blast.
At a news conference held in Chelyabinsk on Friday, the acting head of the regional branch of the Emergency Situations Ministry, Yuri Burenko, suggested that the meteor might be connected with the passing of an asteroid, known as 2012 DA14, near the Earth.
Sergei Smirnov, a senior researcher with the Pulkovo Observatory, near St. Petersburg, concurred that the passing asteroid might be the source of the meteor.
"According to the video footage we received from the Urals, we are dealing with a very bright bolide [fireball] clearly seen in the morning sky as a very big object causing electromagnetic effects and a shock wave, sending its destructive debris over quite a large territory," Smirnov said in an interview on Russia-24. "It is very good that now video testimony can be collected ... which can help to calculate the trajectory of its flight."
It is still early to speak about the composition of the meteor, which can consist of rock, metal or ice, before parts of it are found and studied, Smirnov added.