Critical Mass is an event that brings bike enthusiasts together every month in hundreds of cities around the world to advocate for sustainable transportation. The bikers meander through streets and sometimes block traffic, which can tick off drivers. In Puerto Alegre, Brazil on Friday night, motorist Richard Neis got way more than ticked off. Neis tailed the Critical Mass bikers for some distance in his black VW Golf before gunning the engine and plowing into them.

Neis later ditched his car but decided to give himself up to authorities, according to the Going Going Bike blog, which also reported the following:

A statement made by Mr Neis' lawyer, Luis Fernando Coimbra Albino, contends that Mr Neis ploughed through the cyclists after being threatened by riders at the back of the ride.

Mr Neis was travelling with his 15 year old son in his car and Mr Albino said the instinct to protect his son may have motivated Mr Neis' actions.

According to reports in Brazilian newspaper Zero Hour, Mr Neis' son said that a number of cyclists had been banging on the sides of the Golf and his father had driven away at speed to get away from those people.

Sky reports that at least nine people were injured.

Shock as car ploughs into critical mass ride [Going Going Bike]