A series of explosions in the skies of Russia’s Urals region, reportedly caused by a meteor shower, has sparked panic in three major cities. Witnesses said that houses shuddered, windows were blown out and cellphones stopped working.

Atmospheric phenomena have been registered in the cities of Chelyabinsk, Yekaterinburg and Tyumen.

In Chelyabinsk, witnesses said the explosion was so loud that it resembled an earthquake and thunder at the same time, and that there were huge trails of smoke across the sky. Others reported seeing burning objects fall to earth.

Office buildings in downtown Chelyabinsk are being evacuated. The regional Emergency Ministry said the phenomenon was a meteorite shower, but locals have speculated that it was a military fighter jet crash or a missile explosion.

 

“According to preliminary data, the flashes seen over the Urals were caused by [a] meteorite shower,” the Emergency Ministry told Itar-Tass news agency.

Many locals reported that the explosion rattled their houses and smashed windows.

“This explosion, my ears popped, windows were smashed… phone doesn’t work,” Evgeniya Gabun wrote on Twitter.

“My window smashed, I am all shaking! Everybody says, that a plane crashed,” Twitter user Katya Grechannikova reported.

Many speculated on what caused the powerful explosion — some claimed it was a crashed plane, while others said it could have been a UFO.