A very strange clip has appeared on social media showing a man with an anomalous extra limb.

Sometimes when you are out and about you come across something so strange that it not only makes you double take, but compels you to grab your phone and start recording while you still have the chance.

One such moment was recorded recently by a driver in Peterborough, Canada who was waiting at a railway crossing when she noticed something odd about a man who was also waiting nearby.

The man, who was pacing around with his hands in his pockets, appeared to have three legs.

Even weirder was the fact that the man's extra leg had its own extra trouser leg and shoe.

"What the **** am I looking at?" the woman can be heard repeating over and over in the clip.

Exactly who the man was and why he had an extra leg remains unclear.