The detainee is charged with premeditated murder in Wisconsin, where there has been major unrest.
Police in riot gear stormed a rally on Friday, removing hundreds of protesters by truck.
The minor is charged with premeditated murder. It informs the police chief in Antioch, Norman Johnson, to the news agency AP. He has been arrested in the state of Illinois, which is the state of Wisconsin where Kenosha is located.
The two people were killed during a demonstration that took place in the wake of the black man Jacob Blake being shot and wounded by police officers on Sunday. The protesters had taken to the streets in protest of police violence in the United States.
It was the third day in a row that there were demonstrations in Kenosha, and last night it developed into riots and a shooting broke out between different groups of civilians .
Hit by shots
A video shows a man lying on the ground with a weapon. He starts firing at a group of people coming running towards him.
In the video you can hear the person with the weapon say ‘I just killed someone’.
One victim died of gunshot wounds to the head while the other was shot in the chest. A third person has been injured after being shot, but they are not thought to be life-threatening.