GENEVA

The US must hear and address the grievances at the heart of the protests that have erupted in hundreds of the country's cities if it is to move on from its "tragic history of racism and violence," the UN rights chief said Wednesday.

UN High Commissioner for Human Rights Michelle Bachelet said: "The voices calling for an end to the killings of unarmed African Americans need to be heard. The voices calling for an end to police violence need to be heard,

"And the voices calling for an end to the endemic and structural racism that blights US society need to be heard," Bachelet said in a statement.

"At all times, but especially during a crisis, a country needs its leaders to condemn racism unequivocally, for them to reflect on what has driven people to boiling point, to listen and learn, and to take actions that truly tackle inequalities," she said.

Bachelet repeated calls to protesters to express their demands for justice peacefully and for the police to take the utmost care not to inflame the situation through excessive force.

The protests began in response to the killing of an African-American man, George Floyd, while in police custody on May 25 and have continued, spreading to more than 300 US cities.

Bachelet said she was deeply concerned after statements that have sought to label protesters as terrorists or to delegitimize the mass outpouring of grief and peaceful protest by pointing to violence or destruction of property that has occurred in many locations.

"There can be no doubt as to what or who is 'behind' these protests. We have seen thousands upon thousands of peaceful protesters, of diverse backgrounds, taking to the streets to demand their rights and to call for change,

"Many police officers, as well as National Guard troops, have also responded peacefully to those gathered on the streets," Bachelet said.

The high commissioner said there were credible reports of "unnecessary and disproportionate" use of force by law enforcement officers, including indiscriminate and improper use of less-lethal weapons and ammunition.

Tear gas has been used to disperse peaceful demonstrators and rubber bullets and pepper balls have been fired at demonstrators and journalists who did not pose an imminent threat of serious injury.

"These tactics have been used in some instances in which many victims were retreating," said Bachelet.

There have been at least 200 reported incidents of journalists covering the protests being physically attacked, intimidated or arbitrarily arrested despite their press credentials being clearly visible," said Bachelet.

"What has been happening is an unprecedented assault on journalists [...] It is all the more shocking given that freedom of expression and the media are fundamental principles in the US, central to the country's identity."

The US has been facing protests since last week when a video went viral showing Floyd being pinned down by Derek Chauvin, a white police officer in Minneapolis, Minnesota, as he was being arrested.

Chauvin knelt on his neck for nearly nine minutes.

Shortly after, Floyd appeared to lose consciousness, but Chauvin maintained his position on the victim.

He died shortly after being taken to a hospital.

His last words were "I can't breathe," which became a slogan for nationwide protests.

An independent autopsy on Monday found that Floyd was killed by "asphyxiation from sustained pressure."