A man sacked as a police officer following the death of unarmed black man George Floyd in the US city of Minneapolis has been arrested, officials say.
Derek Chauvin is one of four police officers who were fired after Mr Floyd’s death in custody on Monday.
There have been days of protests, looting and arson after an officer was filmed kneeling on George Floyd’s neck.
Mr Chauvin has been charged with murder and manslaughter.
The case has added to US anger over police killings of black Americans.
On Thursday, during the third night of protests over Mr Floyd’s death, a police station was set alight. A number of buildings have been burned, looted and vandalised in recent days, prompting the activation of the state’s National Guard troops.
There have also been demonstrations in other US cities, including New York, Los Angeles, Chicago, Denver, Phoenix and Memphis.
Earlier on Friday, Minnesota Governor Tim Walz said he expected “swift and fair” justice for Mr Floyd’s death.
President Donald Trump said “thugs” were dishonouring Mr Floyd’s memory and called on the National Guard to restore order.
Social media network Twitter accused Mr Trump of glorifying violence in a post that said: “When the looting starts, the shooting starts.”
What happened to George Floyd?
Officers responding to reports of the use of counterfeit money approached Mr Floyd in his vehicle on Monday.
According to police, he was told to step away from the car, physically resisted officers, and was handcuffed.
Video of the incident does not show how the confrontation started, but a white officer can be seen with his knee on Mr Floyd’s neck, pinning him down.
Mr Floyd can be heard saying “please, I can’t breathe” and “don’t kill me”.
The Minnesota police handbook states that officers trained on how to compress the neck without applying direct pressure to the airway can use a knee under its use-of-force policy. This is regarded as a non-deadly-force option.