In March, researchers from Cambridge University published a study that suggested 50% of Chicago's residents will witness a shooting before their 40th birthday. It's an unfortunate reality that was further illustrated on social media with a clip of three masked men pursuing their target. All three of the assailants were armed; one had an assault rifle. The video shows the perpetrators close in on their target while a witness on a bike slowly backs out of the frame. 

Scroll up to take a look.

Source: Twitter