KENOSHA, Wis. (NewsNation) — Illinois police arrested a 17-year-old Wednesday after two people were shot to death during another night of protests in Kenosha, Wisconsin, over the shooting of Jacob Blake by police.

Kyle Rittenhouse from Antioch, Illinois, was arrested suspicion of first-degree intentional homicide, the Antioch Police Department said.

Antioch is about 15 miles from Kenosha, which has seen three straight nights of unrest since police shot Jacob Blake, a Black man, in a confrontation captured on cellphone video.

Gunfire erupted just before midnight Tuesday, and one person was shot in the head while another person was shot in the chest, Kenosha County Sheriff David Beth told the Milwaukee Journal Sentinel. The third person is in serious condition at a local hospital with injuries that aren’t considered life-threatening, police said.

The victims have not yet been identified.

Rittenhouse is now being held at a juvenile detention facility in Lake County, Illinois. He was denied for bond on Wednesday, according to Lake County Illinois Circuit Court Records. Rittenhouse’s next court appearance is an extradition hearing scheduled for Friday to get him moved to Wisconsin to face the more severe charges.

According to witness accounts and video footage, police apparently let Rittenhouse, who was suspected in the attack walk past them with a rifle over his shoulder as members of the crowd were yelling for him to be arrested because he had open fired in the middle of the street.

The sheriff told the Journal Sentinel that armed people had been patrolling the city’s streets in recent nights, but he did not know if the teen was among them.

“They’re a militia,” Beth said. “They’re like a vigilante group.”

In Wisconsin, it is legal for people 18 and over to openly carry a gun, with no license required.

The FBI said it is assisting in the case. It remains unclear if police are searching for more suspects in the shooting.

Witness accounts and video show that the shootings took place in two stages: The gunman first shot someone at a car lot, then jogged away, stumbled and fell in the street, and opened fire again as members of the crowd closed in him.

A witness, Julio Rosas, 24, said that when the gunman stumbled, “two people jumped onto him and there was a struggle for control of his rifle. At that point during the struggle, he just began to fire multiple rounds and that dispersed people near him.”

“The rifle was being jerked around in all directions while it was being fired,” Rosas said.

Sam Dirks, 22, from Milwaukee, said he saw what is now suspected to be Rittenhouse earlier in the evening, and he was yelling at some of the protesters.

“He was definitely very agitated. He was pacing around, just pointing his gun in general. Not necessarily at anyone specifically,” Dirks said.

In the wake of the killings, Wisconsin Gov. Tony Evers authorized 500 members of the National Guard to support local law enforcement around Kenosha, doubling the number of troops sent in. The governor’s office said he is working with other states to bring in additional National Guard troops and law officers.

The unrest comes after Blake was shot by police at least seven times, according to his family. Bullets pierced Blake’s spine and shattered one of his ribs, puncturing a lung, according to attorney Ben Crump.

Crump, who represents the family, said Blake was trying to de-escalate a domestic incident and that his three children – aged 3, 5 and 8 – were inside the car at the time of the shooting.

Kenosha police have said little about what happened as their investigation into the shooting continues, except that they were responded to a domestic dispute. They have not said why the officers opened fire or whether Blake was armed, and they have not disclosed the race of three officers on the scene.

The shooting was captured on cellphone video and ignited new protests in the U.S. three months after the death of George Floyd under the knee of a Minneapolis police officer touched off a nationwide reckoning over racial injustice.