This shocking footage shows the moment a man is brutally headbutted to the floor in the middle of a busy fast-food restaurant.

Recorded last Friday, the shocking clip shows men brawling at a Roosters Piri Piri restaurant in Watford as onlookers look on in horror.

As the violence inside the restaurant gets worse, one of the men is knocked to the ground by the force of a headbutt.

Watford Observer:

Despite the attack, the man manages to get back to his feet before the pair grapple around the restaurant, smashing into tables and windows as fellow diners watch on.

The footage was uploaded to Facebook page "Savage Sundays" with the caption: "savage headbutt but that's none of my business."

It already been viewed 63,000 times with a further 530 shares and 580 comments.

The 95-second-clip starts as one man removes his suit jacket and says: "Do you want to speak to me like that again?"

Watford Observer:

He then walks over to the other man, who has his back to him as he orders his food, before unleashing a brutal headbutt as he turns around.

The sickening crack and gasps of onlookers can be heard as the man falls to the ground.

However, he immediately gets back up and begins to grapple with the other man, getting him in a headlock.

The pair then move around the restaurant , as two females, one still holding her sandwich, try to intervene and stop the fight.

Watford Observer:

Both men then swing punches wildly at each other, before crashing into the glass entrance, as blood starts to pour from the headbutted man's nose and covers the other's white shirt.

The headbutted man manages to pin him in a hold by the door and asks him: "Do you think you're a man. Why the f**k are you attacking me? Can you calm down?"

They are eventually separated and the footage ends with the headbutted man holding a tissue to his nose and the other walks out of the restaurant in his blood-soaked shirt.

Facebook users were quick to comment on the shocking footage.

Jack Breathet wrote: "Headbutt from hell."

A staff member confirmed they were aware of the footage.

Hertfordshire Police also confirmed they were aware of the footage circulating online, but have not received any reports relating to the incident and no arrests had been made.