This is really, really weird: Multiple sightings and dashcam videos of a gigantic yellow flash that covered the skies of the Sverdlovsk region, in Russia, have been reported on the night of November 14th. Scientists and local authorities still don't know what it is or where did it come from.
Here's another video of the mysterious flash that shows it could possibly come from a explosion in the ground.
There are several theories about the origin of this strange phenomena being a meteor, military exercises, or the explosion of a nearby factory the most plausible. But none of them has been confirmed so far.
Russian astronomers don't seem to get to an agreement. While astronomer Vadim Krushinsky points that the colour of the flash discards the meteor theory, his colleague Viktor Grokhovsky, a member of the meteorites committee of the Russian Academy of Sciences, supports it. He told 66.ru(in Russian):
Looks like a falling bolide, which invaded us. Because of the low cloud cover it ceased to exist above the clouds and lit up the whole sky
Russian military press service claims it has nothing to do with it either. They told E1.ru (in Russian):
No exercise and training were underway on that day, and no military units are based in the region.
The factory explosion theory seems very unlikely too. According to RT:
Regional emergency services said no accidents in connection with the event had been recorded. No sound of explosion has been reported either.
Seems that no one has a clue about of what caused this weird flash in the sky. So, until more information arises, my two cents go for the meteor theory.