One year on from the tragic death of Michael Brown and Ferguson devolved into violence again as activities to mark Brown’s anniversary turned into clashes with police.

18 year old African American Tyrone Harris was shot in the confusion, later charged with assaulting police officers, whilst prominent activist Dr Cornel West was also arrested.

According to police, a gunfight erupted between two rival groups in West Florissant Avenue and a suspect, whom they identified as Tyrone Harris, then shot at plain-clothes police who returned fire.

Police Chief Belmar said those who had opened fire on the officers “were criminals, they weren’t protesters”.

But Mr Harris’s father described the police account as “a bunch of lies”, saying his son had been unarmed and was “running for his life”.

The state of emergency was issued on Monday afternoon by St Louis County Executive Steve Stenger and authorised county Police Chief Jon Belmar to take control in and around Ferguson, reports the BBC.

Late on Monday, police arrested several protesters who blocked a traffic lane on West Florissant Avenue – the site of previous unrest. Witnesses said some people in the crowd threw water bottles at officers but there were no reports of violence.

Police also arrested about 50 protesters – including civil rights activist Cornel West – who staged a sit-in outside the main courthouse in St Louis.

Other protesters also briefly blocked a major highway – Interstate 70 – during the afternoon rush hour and a number of arrests were made.

The demonstrations were part of a day of civil disobedience called by activists in St Louis and other major US cities.

Michael Brown, 18, was shot in August 2014 by a white police officer who was later cleared of any wrongdoing by a grand jury and the US Department of Justice.