A middle-aged man, believed to be a hawker, was shot in broad daylight by a police officer during Tuesday's protests in Nairobi's Central Business District, as crowds marched to demand justice for slain teacher and blogger, Albert Ojwang.

What began as a peaceful protest quickly descended into chaos.  Groups of men, some armed with wooden clubs and believed to be hired goons, surged through the streets in an unruly procession.  Motorbike riders soon joined the melee, and what followed was a violent clash with demonstrators.

Police responded with teargas, batons, and live bullets.  Among the victims was the hawker seen moments earlier holding a bunch of face masks and engaging two armed police officers.  Witnesses say a brief argument broke out before one of the officers pulled the trigger.  The man collapsed with a sickening thud, his body left sprawled on Moi Avenue as stunned protestors screamed in horror and photojournalists clicked away.

Graphic images of the shooting, captured in real-time, have sparked national outrage and renewed scrutiny of police conduct during protests.