The police chief in the US city of Rochester resigned on Tuesday, following days of protest over the death of a black man whom police had hooded and forced face-down on a road.

The arrest of Daniel Prude took place in March, but his family and activists made his death public last Wednesday, after receiving bodycam footage through an open records request.

When officers arrived, the 41-year-old Prude – who was suffering from a psychotic episode at the time – was unarmed and naked in the road, according to the video.

Police ordered an initially compliant Prude to get on the ground, but after being handcuffed he became increasingly agitated.

Officers then put a “spit hood” on him, because he said he had contracted the coronavirus, and forced his head to the pavement. Moments later he lost consciousness.

He died in a hospital a week later, when life support was switched off.

The seven officers present were all suspended and an investigation into the event is underway by New York state Attorney General Letitia James.

In a statement, Rochester police chief La’Ron Singletary said the accusations about his lack of initiative in the matter and alleged attempts to cover up the case were a “mischaracterisation” and slammed the “politicisation” of his actions.

“As a man of integrity, I will not sit idly by while outside entities attempt to destroy my character,” said Singletary, who is black.

Singletary, 40, was named as police chief of Rochester in April last year. He spent 20 years on the city’s police force before retiring on Tuesday.

Attorney General James announced on Saturday she would form a grand jury to probe Prude’s death, a preliminary step to a possible indictment.

Local media said an autopsy ruled the death a homicide caused by “complications of asphyxia in the setting of physical restraint”.

The report also listed a low level of the drug PCP in Prude’s blood.

The revelation of Prude’s death sparked protests in Rochester and New York City demanding justice for the victim and reforms in the Rochester police department.

Prude’s death has grim echoes of those of George Floyd and Breonna Taylor, also black Americans who died in police incidents and whose deaths unleashed a wave of anti-racism demonstrations that have rocked the US since May.