Updated 5.29pm

A female cyclist in London infuriated by a catcaller's sexist taunts chased after the van he was riding in and ripped off its side mirror. 

The misogynistic outburst was caught on a helmet camera worn by a motorcyclist riding behind the two protagonists. More than 10 million people watched the video within 24 hours of it being uploaded. 

But according to UK newspaper The Sun, an eyewitness has claimed that the event was staged. 

The man claimed that he saw actors receive instructions before the scene was filmed.

"They practiced the scene two or three times with the motorbike riding behind them," the man said. 

In the video, the passenger can be heard hurling abuse at the cyclist, who bangs the side of the van and tells them to leave her alone as they wait for traffic lights to turn green. 

"Shut up you old dog. Are you on your period?" the man asks the insulted woman before going on to ask her out for a drink. 

As the van speeds off, the woman furiously pedals behind the van, and the motorcyclist filming follows suit. 

When the van pulls over, the cyclist stops alongside the van's driver side door and wrenches the side mirror off, dropping it onto the ground before pedalling away. 

The motorcyclist gasps before pulling alongside the van and letting its driver and passenger know what he thinks. 

"That's exactly what you deserve, you scum!" he spits out. 

A 2016 survey found that 85 per cent of women in the UK have been sexually harassed in public. 

In Malta, a 2014 study conducted by the European Union Agency for Fundamental Rights found that one in every five women had experienced some form of sexual harassment during the previous 12 months.