A video showcasing three lights moving in the sky has led to many speculating whether a spy "TR-3B" type UFO flew over Russia last week.

YouTube channel UFO Today posted the video and wrote: “The object is moving at a very slow pace, too slow to be classic airplane.

“The speed at which this object was moving is physically impossible for any airplane build by mankind.

“At a certain point in time the aircraft loses propulsion in one of the three engines, but that does not stop it.

“It continues its way through earth's skies.

“Reports generally describe this class of UFOs as large, silent, black triangular objects hovering or slowly cruising at low altitudes over cities and highways.

“Sightings usually take place at night. These objects are often described as having pulsing coloured lights that appear at each corner of the triangle.”

TR-3B is alleged by conspiracy theorists to be a secret "black project" spy craft of the US Government that can be flown into space.

To read more and view the video, click here.