Wisconsin’s attorney general has named the officer who shot a black man on Sunday, sparking days of demonstrations.
Josh Kaul told reporters on Wednesday that Rusten Sheskey shot Jacob Blake seven times in the back as he opened the door of his car.
Officers found a knife in Mr Blake’s car, he added, but no other weapons.
The shooting has sparked a wave of protests in recent days, some of which have turned violent.
A 17-year-old was arrested on Wednesday after two people were killed and another injured amid unrest on Tuesday night.
Mr Blake is recovering in hospital and is conscious, but his lawyers fear it will take a “miracle” for him to walk again.
US President Donald Trump has since sent federal law enforcement to Kenosha, tweeting they were to combat “looting, arson, violence, and lawlessness on American streets”.
The Department of Justice has opened a federal investigation into the shooting. It has sent more than 200 FBI agents and US Marshals to the city, according to a spokeswoman.
Shortly after Mr Trump’s tweet, Wisconsin Governor Tony Evers said he had authorised 500 National Guard troops to support law enforcement efforts amid concerns about further violence.
Protests have also spread to a number of other US cities, including Portland, Oregon and in Minneapolis, Minnesota, where the police killing of unarmed black man George Floyd in May sparked Black Lives Matter protests across the US and globally.
