A spectacular meteor shower has rained down on central Russia, injuring several people and shattering windows, reports say.
There was panic on the streets as many buildings were evacuated, following powerful blasts as the meteors hurtled across the sky over the Urals region.
"A meteorite disintegrated above the Urals, partially burning up in the lower atmosphere," AFP reported the local office of the national emergencies ministry as saying.
"Fragments of the meteorite reached Earth, falling in sparsely populated areas in the Chelyabinsk region.
"According to preliminary information, four people have been injured by flying glass."
The statement said "numerous calls of panic" had been received.
Explosions were reported and shockwaves from the blasts reportedly blew out several windows, with the interior ministry saying several people were injured by flying glass at a school in Chelyabinsk.
Numerous videos have been posted on YouTube showing burning mounds of rock shooting through the sky, leaving trails of smoke in their wake. One shows glass from windows of a building smashing onto the street before dozens of people are evacuated as they try to establish what is going on.
Local residents said they witnessed burning objects in the sky of the Chelyabinsk and Sverdlovsk regions.
A Reuters witness in Chelyabinsk reported hearing a huge blast early in the morning and feeling a shockwave in a 19-storey building in the town centre.
The sounds of car alarms and breaking windows could be heard in the area, the witness said, and mobile phones were working intermittently.
The trace from a falling object could be seen in Yekaterinburg, some 200 kilometers southeast of Chelyabinsk, another Reuters witness said.