The huge 26 feet across burning pit was filmed by shocked onlookers as a thick mist rose into the air by the Torreón to Saltillo highway in the state of Coahuila in north east Mexico.

It was said to be as deep as it was wide and, according to reports, no evidence has been found as to what caused it.

Online theories have ranged from a crashed spaceship or a meteor falling to Earth.

It happened on January 17 and the video was uploaded to YouTube the next day, before racking up tens of thousands of views, Dailystar.co.uk reports.

One YouTube poster said: "Looks like a UFO landed and took off before anyone could see, leaving a crater.”

Another viewer said: “It’s a burning hole. Does not look like an impact to the earth as there is no debris.”

It is not the first mystery burning hole to have been found in Mexico.