Police in Wisconsin imposed a curfew on the city of Kenosha after a night of unrest over the shooting of an apparently unarmed Black man as he got into his car.

Officers used tear gas in the early hours of Monday to break up hundreds of people who had taken to the streets. Police said some protesters had thrown bricks and Molotov cocktails at them.

Police wearing riot gear deployed in lines near public buildings and armored rescue vehicles remained in place after a curfew was imposed until 7 a.m. 

A video posted on social media showed the shooting, with three officers pointing their weapons at the man, identified as Jacob Blake. They appeared to have shot the man several times as he opened the driver's side door of a vehicle and leaned into it.

The Kenosha Police Department said the officers were responding to a domestic incident. The department did not provide more details of what led to the shooting, but said Blake had been transferred to a hospital in Milwaukee for treatment.

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The Wisconsin Department of Justice early on Monday said the officers involved in the shooting had been placed on administrative leave.

State Governor Tony Evers said the circumstances of the shooting raised serious questions about law enforcement.

"Jacob Blake was shot in the back multiple times, in broad daylight, in Kenosha, Wisconsin," said Evers. "While we do not have all of the details yet, what we know for certain is that he is not the first Black man or person to have been shot or injured or mercilessly killed at the hands of individuals in law enforcement in our state or our country."

Demonstrations against police brutality and racism have swept the US since thedeath in May of George Floyd. The 46-year-old Black man died after a Minneapolis police officer knelt on his neck for nearly nine minutes.

rc/rt (AP, Reuters)