Eyewitnesses describe seeing a fireball curving through the clear sky, and an extremely intense light as it passed overhead. It seems to have been a meteor, and left a white condensation trail behind it. A couple of minutes later there was a loud bang. The shock wave from the blast blew out windows across the region around Chelyabinsk in the Ural mountains. People who'd rushed to look out and see what was happening were injured by flying glass. Everyone went outside to check their neighbours were okay, and the mobile phone network collapsed, briefly overwhelmed by the volume of calls.