A meteor streaked across the sky and exploded over central Russia on Friday, sending fireballs crashing to earth which shattered windows and damaged buildings, injuring more than 500 people.
People heading to work in Chelyabinsk heard what sounded like an explosion, saw a bright light and then felt a shockwave, according to a Reuters correspondent in the industrial city 1,500 km (950 miles) east of Moscow.
The fireball, travelling at a speed of 30 km (19 miles) per second according to Russia's space agency Roscosmos, had blazed across the horizon, leaving a long white trail in its wake which could be seen as far as 200 km (125 miles) away.
Car alarms went off, windows broke and mobile phone networks were interrupted. The Interior Ministry said the meteor explosion had caused a sonic boom.
"I was driving to work, it was quite dark, but it suddenly became as bright as if it was day," said Viktor Prokofiev, 36, a resident of Yekaterinburg in the Urals Mountains.
"I felt like I was blinded by headlights," he said.
No fatalities were reported, but President Vladimir Putin, who was due to host Finance Ministry officials from the Group of 20 nations in Moscow, told Emergencies Minister Vladimir Puchkov to help those affected.
"Unfortunately, the normal work of some industrial enterprises was disrupted, people have suffered as has social infrastructure - kindergartens, schools," Putin told his Emergencies Minister Sergei Puchkov in televised comments.
"First of all, it is necessary to think about how to help the people, and not only to think about it, but to do it immediately," Putin said.
A local ministry official said such incidents were extremely rare and Friday's events might have been linked to an asteroid the size of an Olympic swimming pool due to pass earth. However, the European Space Agency on its Twitter website said its experts had confirmed there was no connection.
"There have never been any cases of meteorites breaking up at such a low level over Russia before," said Yuri Burenko, head of the Chelyabinsk branch of the Emergencies Ministry.
Russia's Emergencies Ministry said 514 people had sought medical help, mainly for light injuries caused by flying glass, and that 112 of them were kept in hospital.
Despite warnings not to approach any unidentified objects, some enterprising locals were hoping to cash in.
"Selling meteorite that fell on Chelyabinsk!," one prospective seller, Vladimir, said on a popular Russian auction website. He attached a picture of a black piece of stone that on Friday afternoon was priced at 1,488 roubles (32 pounds).
WINDOWS BREAK, FRAMES BUCKLE
The blast at around 9.20 a.m. shattered windows on Chelyabinsk's central Lenin Street and some of the frames of shop fronts buckled. The shockwave could be felt in apartment buildings in the city's centre.
"I was standing at a bus stop, seeing off my girlfriend," said Andrei, a local resident who did not give his second name. "Then there was a flash and I saw a trail of smoke across the sky and felt a shockwave that smashed windows."
Chelyabinsk city authorities urged people to stay indoors unless they needed to pick up their children from schools and kindergartens. They said what sounded like a blast had been heard at an altitude of 10,000 metres (32,800 feet).
A wall was damaged at the Chelyabinsk Zinc Plant but a spokeswoman said there was no environmental threat.
Although a rare occurrence, a meteorite is thought to have devastated an area of more than 2,000 sq km (1,250 miles) in Siberia in 1908, smashing windows as far as 200 km (125 miles) from the point of impact.
The Emergencies Ministry described Friday's events as a "meteor shower in the form of fireballs" and said background radiation levels were normal. It urged residents not to panic.
Simon Goodwin, an astrophysics expert from Britain's University of Sheffield, said it was estimated between 1,000 and 10,000 tonnes of material rained down from space onto the earth every day, but most burned up in the atmosphere.
"While events this big are rare, an impact that could cause damage and death could happen every century or so," he said. "Unfortunately there is absolutely nothing we can do to stop impacts."
The meteor struck just as an asteroid known as 2012 DA14, about 46 metres in diameter was due to pass closer to earth than any other known object of its size since scientists began routinely monitoring them about 15 years ago.
The small asteroid was expected to pass at a distance of 27,520 km (17,100 miles) from earth on Friday.
(Additional reporting by Gabriela Baczynska in Moscow, Writing by Alexei Anishchuk and Timothy Heritage, Editing by Michael Holden)
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