MINNEAPOLIS • A third night of racially charged arson, looting and vandalism gripped Minneapolis as protesters vented rage over the death of an unarmed black man following his arrest by the police.

The latest unrest in Minnesota's largest city went largely unchecked late on Thursday, with the mayor ordering a tactical police retreat from a police station that was set ablaze.

National Guard troops called out earlier in the day by Governor Tim Walz also kept a low profile.

In contrast with Wednesday night when protesters clashed with police, law enforcement kept mostly out of sight around the epicentre of Thursday's disturbances - the Third Precinct police station.

Protesters outside the police building briefly retreated under volleys of tear gas and rubber bullets, only to regroup and eventually set fire to the building as police officers withdrew.

The unrest in the United States was sparked by Mr George Floyd's death on Monday. The arrest of Mr Floyd, 46, was captured by an onlooker's mobile phone video that showed a police officer pressing his knee into Mr Floyd's neck as he moaned: "Please, I can't breathe." He was accused of trying to pass counterfeit money at a store.

Four officers were dismissed, but the unrest has continued.

Thursday night's disturbances in Minneapolis spread to the adjacent city of St Paul, with fires and vandalism breaking out there. Sympathy protests also erupted in Denver on Thursday and in Los Angeles on Wednesday.

Early yesterday morning in Minneapolis , police arrested a CNN reporter reporting live on television and led him and three crew members away in handcuffs. Black reporter Omar Jimenez and his crew were later released.

In Geneva, United Nations rights chief Michelle Bachelet on Thursday demanded that the US take "serious action" to stop the killings of unarmed African Americans.

REUTERS, AGENCE FRANCE-PRESSE