President Joe Biden is urging protests in Tennessee to remain peaceful as officials plan to release video of an arrest that led to a motorist’s death.
Bodycam video of the encounter with Tyre Nichols, 29, will be published on Friday and lawyers for his family said it will show him being severely beaten.
Five now-fired police officers face murder charges after Mr Nichols died days after a traffic stop 7 January.
Memphis is said to be on edge and police there have increased patrols.
“I’m sickened by what I saw,” Tennessee Bureau of Investigation director David Rausch said on Thursday after reviewing the footage, describing the officers’ actions as “absolutely appalling”.
Mr Nichols, a black man, was stopped by five police officers, who are also black, on his way home after taking photos of a sunset at a local park, an attorney for the family said.
Officials say he was suspected of reckless driving.
A first confrontation occurred as Mr Nichols attempted to flee on foot when officers approached his car, the local authorities said.
They said a second confrontation happened when officers tried to arrest him.
Mr Nichols later complained of shortness of breath and was taken to hospital, police said, where he was listed in a critical condition.
A lawyer for Mr Nichols’ family said the bodycam footage showed Mr Nichols being pepper-sprayed, struck with a stun gun, restrained and kicked.
He likened the incident to the notorious footage of Los Angeles police officers beating black motorist Rodney King more than 30 years ago.
All five of the officers face charges of second-degree murder, aggravated assault, aggravated kidnapping, official misconduct and official oppression.
Tadarrius Bean, Demetrius Haley, Desmond Mills Jr, Emmitt Martin III and Justin Smith were booked into jail on Thursday. They all joined the Memphis Police Department in the last six years, and were fired last week.