Five ex-police officers have been charged with second-degree murder after a man died following a traffic stop in Memphis, Tennessee.
Tyre Nichols, 29, who was black, died three days after his arrest on 7 January for alleged reckless driving.
The officers, who are all black, also face charges of aggravated assault, aggravated kidnapping, official misconduct and official oppression, BBC news reports.
The family of Nichols said an autopsy indicates he was severely beaten.
US President Joe Biden called for "peaceful protest" as authorities prepare to release the footage on Friday evening local time.
The city's police chief earlier also urged people to remain calm once the clip is made public.
"This is not just a professional failing," Cerelyn Davis, who is the first black woman to serve as the city's police chief, said of the ex-officers' alleged conduct.
"This is a failing of basic humanity toward another individual."
The five officers, all of whom joined the Memphis Police Department in the last six years, were fired last week after an investigation found them to be "directly responsible for the physical abuse of Nichols".
Tadarrius Bean, Demetrius Haley, Desmond Mills Jr, Emmitt Martin III and Justin Smith are all in custody, jail records show.
In a news conference on Thursday, lawyers for two of the men said their clients planned to fight the charges.
Blake Ballin, an attorney for Mills, said: "Knowing Mills and the kind of person he is, I cannot imagine he has anything but feelings of grief for the [Nichols] family."
A lawyer for Martin said the death was "shocking to officers".
"No-one out there that night intended for Tyre Nichols to die," said the attorney, William Massey.
The Nichols family and their legal team privately reviewed the video footage of the arrest earlier this week.
"He was a human piñata," lawyer Antonio Romanucci said of its contents. "It was an unadulterated, unabashed, non-stop beating of this young boy for three minutes."
On Wednesday, the family's lawyers said a post-mortem examination indicated he had been severely beaten.
"My son was a beautiful soul," said Nichols' mother, Rowvaughn Wells. "Nobody is perfect, but he was damn near." She called her son's death a "murder".
Activists hold signs showing Tyre Nichols as attorney Ben Crump is seen speaking on a monitor during a press conference Image source, Getty Images
Nichols was stopped by police on his way home after taking photos of a sunset at a local park, an attorney for the family said.
The lawyer said after reviewing the footage that it shows Nichols being pepper-sprayed, tasered, restrained and kicked.
City officials said police officers pulled him over for reckless driving and two "confrontations" occurred.
According to authorities, the first happened as officers approached the vehicle and he attempted to flee on foot.
They said the second confrontation happened when officers tried to arrest him.
Nichols later complained of shortness of breath and was taken to hospital, police said, where he was listed in a critical condition.
Officials said Nichols "succumbed to his injuries" on January 10, but provided no further detail. An official cause of death has not yet been disclosed.
Reverend Al Sharpton, a US civil rights leader, told BBC News the crime was particularly painful because of the race of the officers.
"We fought to put blacks on the police force," he said. "For them to act in such a brutal way is more egregious than I can tell you."
Sharpton also said he believes the outcome would have been different if the alleged victim in the incident was white.
"I do not believe these five black police officers would have done this had he been a young white man," he said.
The FBI and the Department of Justice have opened a civil rights investigation into Mr Nichols' death.
In a statement, President Biden sent condolences to the victim's family and the entire city of Memphis.
"As Americans grieve, the Department of Justice conducts its investigation, and state authorities continue their work, I join Tyre's family in calling for peaceful protest," he said.
"Outrage is understandable, but violence is never acceptable."