Officers in riot gear have clashed with demonstrators in Albuquerque after video emerged of police shooting dead a homeless man.

Police fired tear gas, charged at protesters and made several arrests after the 10-hour demonstration in the New Mexico city on Sunday.

Albuquerque Mayor, Richard Berry, said the protest had turned from peaceful into "mayhem".

"We respected their rights to protest obviously" Mr. Berry said, "but what it appears we have at this time is individuals who weren't connected necessarily with the original protest. They've taken it far beyond a normal protest" he added.

The protesters blocked traffic, tried to get on freeways and shouted anti-police slogans. Gas canisters were thrown outside police headquarters, while rocks were hurled at officers, with at least one injured, according to news reports.

People are angry over Albuquerque Police's involvement in 37 shootings - 23 of them fatal - since 2010.

One shooting in particular, that of homeless camper James Boyd in the city's foothills, has outraged citizens. The March 16th incident was captured on video and followed a long stand-off.

Police released the video, taken from a helmet camera, and insisted the shooting was justified. They said they wanted Mr. Boyd to move and stop illegally camping in an open space, but he refused to comply and threatened police.

The FBI has opened an investigation.