BBC – A former Minneapolis police officer has been arrested and charged with murder following the death of an unarmed black man in custody.

Derek Chauvin, who is white, was shown in footage kneeling on 46-year-old George Floyd’s neck on Monday. He and three other officers have been sacked.

Days of looting and arson in the Minnesota city have boiled over into nationwide protests.

The case has reignited US anger over police killings of black Americans.

What did the prosecutor say?

Hennepin County Prosecutor Mike Freeman said Mr Chauvin was charged with third-degree murder and second-degree manslaughter.

He said he “anticipates charges” for the three other officers but would not offer more details.

Mr Freeman said his office “charged this case as quickly as evidence has been presented to us”.

“This is by far the fastest that we’ve ever charged a police officer,” he noted.

According to the criminal complaint, Mr Chauvin acted with “a depraved mind, without regard for human life”. 

What’s the latest on the protests?

On Friday evening, the White House was placed on lockdown after a protest was held outside. “I can’t breathe,” demonstrators could be heard chanting, invoking the last words of Mr Floyd and Eric Garner, a black man who died after being held in a police chokehold in New York in 2014.

Curfews have been ordered for the so-called Twin Cities of Minneapolis-Saint Paul, from 20:00 to 06:00 starting on Friday night and ending Sunday morning.

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 elsewhere, including New York, Los Angeles, Chicago, Denver, Houston, Atlanta, Louisville, Phoenix, Columbus and Memphis.

Frustration was already simmering over the recent deaths of two other black Americans, Ahmaud Arbery in Georgia and Breonna Taylor in Kentucky.

How did George Floyd die?

The full report by the county medical examiner has not been released, but the complaint states that the post-mortem examination did not find evidence of “traumatic asphyxia or strangulation”.

The medical examiner noted Mr Floyd had underlying heart conditions and the combination of these, “potential intoxicants in his system” and being restrained by the officers “likely contributed to his death”.

The report says Mr Chauvin had his knee on Mr Floyd’s neck for eight minutes and 46 seconds – almost three minutes of which was after Mr Floyd became non-responsive.

Nearly two minutes before he removed his knee the other officers checked Mr Floyd’s right wrist for a pulse and were unable to find one. He was taken to the Hennepin County Medical Center in an ambulance and pronounced dead around an hour later.