Shocking footage has captured the moment a man with a shovel smashed the rear-view window of a car which reportedly had a newborn baby inside.

The dramatic video, taken in Chequers Lane near Abbots Langley, shows what appears to be an argument breaking out between the man and the occupants of a BMW before the apparent act of road rage.

The video taken from another car begins with a woman getting out of the BMW as a man with a shovel walks up to the car from a van.

Footage shows her running over to the man and speaking to him before getting back into the BMW.

Watford Observer: Photo credit: Jason BoggelnPhoto credit: Jason Boggeln

A man in a red top, said to have been a neighbour helping to try and calm the situation, appears to then walk up to the man with the shovel to hold him back.

Another man at the scene is also said to have been trying to calm the situation.

But the man with the shovel is captured banging on the door of the car before making hand gestures.

As the BMW then drives off, the man proceeds to smash the rear windscreen of the car before walking back to the van.

Watford Observer: Photo credit : Jason BoggelnPhoto credit : Jason Boggeln

Watford Observer: Photo credit: Jason BoggelnPhoto credit: Jason Boggeln

The video was uploaded to Facebook on Friday afternoon, where the poster reported that a newborn baby was inside the BMW.

The footage has been viewed more than 40,000 times, with people having described the incident as "awful" and "disgusting".

The poster said the incident took place in Chequers Lane which is a narrow country that runs around the outskirts of Garston and out onto the A405 in Bricket Wood.

The motive behind the incident is unclear at this stage.

A Hertfordshire Constabulary spokesperson said: "Police were called at around 12.55pm on Friday 11 June following an incident in Chequers Lane, Abbots Langley.

"It was reported that an altercation had occurred between the occupants of two vehicles, during which a man sustained an injury to his hand.

"The rear windscreen of one of the vehicles was also smashed during the incident.

"Enquiries are continuing at this time to trace those involved. Anyone with information who hasn’t yet spoken to police is asked to please come forward."