A white, 17-year-old police admirer was arrested Wednesday after two people were shot to death during a third straight night of protests in Kenosha over the police shooting of a Black man, Jacob Blake.

Kyle Rittenhouse, of Antioch, Illinois, about 15 miles (24.14 kilometers) from Kenosha, was taken into custody in Illinois on suspicion of first-degree intentional homicide in the attack Tuesday that was largely captured on cellphone video. The shooting left a third person wounded.

“I just killed somebody,” the gunman, carrying a semi-automatic rifle, could be heard saying at one point.

In the wake of the killings, Wisconsin Gov. Tony Evers authorized the deployment of 500 members of the National Guard to Kenosha, doubling the number of troops in the city of 100,000 midway between Milwaukee and Chicago. The governor’s office said he is working with other states to bring in additional National Guard members and law officers. Authorities also announced a 7 p.m. curfew, though protesters ignored it again Wednesday.

Protesters marched past the intersection where two people were shot Tuesday night, stopping to gather around the spot where one person was shot, and to pray and lay flowers. Daijon Spann said he decided to join the demonstration because one of those killed the night before was a friend.

“I couldn’t take it any more,” he said. “I couldn’t just sit there and watch my friend die.”

Evers, a Democrat, issued a statement asking those who wanted to exercise their First Amendment rights to “please do so peacefully and safely” and urging others to “please stay home and let local first responders, law enforcement and members of the Wisconsin National Guard do their jobs.”

“A senseless tragedy like this cannot happen again,” Evers said.

As of early Thursday, the protests were mostly peaceful, in contrast to the violent clashes that marked earlier nights of protests. There were no groups patrolling with long guns as they had on previous nights, and protesters stayed away from a courthouse that had been the site of standoffs with law enforcement.

In Washington, the Justice Department said it is sending in more than 200 federal agents from the FBI, U.S. Marshals Service and the Bureau of Alcohol, Tobacco, Firearms and Explosives. The White House said up to 2,000 National Guard troops would be made available.

The dead were identified only as a 26-year-old Silver Lake, Wisconsin, resident and a 36-year-old from Kenosha. The wounded person, a 36-year-old from West Allis, Wisconsin, was expected to survive, police said.

“We were all chanting ‘Black lives matter’ at the gas station and then we heard, boom, boom, and I told my friend, `That’s not fireworks,’” 19-year-old protester Devin Scott told the Chicago Tribune. “And then this guy with this huge gun runs by us in the middle of the street and people are yelling, ‘He shot someone! He shot someone!’ And everyone is trying to fight the guy, chasing him, and then he started shooting again.”

Scott said he cradled a victim in his arms, and a woman started performing CPR, but “I don’t think he made it.”

According to witness accounts and video footage, police apparently let the gunman walk past them and leave the scene with a rifle over his shoulder and his hands in the air as members of the crowd were yelling for him to be arrested because he had shot people.

As for how the gunman managed to slip away, Sheriff David Beth described a chaotic, high-stress scene, with lots of radio traffic and people screaming, chanting and running — conditions he said can cause “tunnel vision” among law officers.

Rittenhouse was assigned a public defender in Illinois for a hearing Friday on his transfer to Wisconsin. The public defender’s office had no comment. Under Wisconsin law, anyone 17 or older is treated as an adult in the criminal justice system.

Much of Rittenhouse’s Facebook page is devoted to praising law enforcement, with references to Blue Lives Matter, a movement that supports police. He also can be seen holding an assault rifle.

In a photograph posted by his mother, he is wearing what appears to be a blue law enforcement uniform as well as the kind of brimmed hat that state troopers wear.

The sheriff told the Milwaukee Journal Sentinel that militia members or armed vigilantes had been patrolling Kenosha’s streets in recent nights, but he did not know if the gunman was among them. However, video taken before the shooting shows police tossing bottled water from an armored vehicle to what appear to be armed civilians walking the streets. And one of them appears to be the gunman.

“We appreciate you being here,” an officer is heard saying to the group over a loudspeaker.

Before the shooting, the conservative website The Daily Caller conducted a video interview with the suspected gunman in front of a boarded-up business.

“So people are getting injured, and our job is to protect this business,” the young man said. “And part of my job is to also help people. If there is somebody hurt, I’m running into harm’s way. That’s why I have my rifle — because I can protect myself, obviously. But I also have my med kit.”

Wisconsin Lt. Gov. Mandela Barnes, who is Black, said in an interview with the news program “Democracy Now!” that the shootings were not surprising and white militias have been ignored for too long.

“How many times across this country do you see armed gunmen, protesting, walking into state Capitols, and everybody just thinks it’s OK?” Barnes said. “People treat that like it’s some kind of normal activity that people are walking around with assault rifles.”

In Wisconsin, it is legal for people 18 and over to openly carry a gun without a license.

Witness accounts and video indicate the gunman first shot someone at a car lot just before midnight, then jogged away, fell in the street, and opened fire again as members of the crowd closed in on 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.

Blake, 29, was shot in the back seven times on Sunday as he leaned into his SUV, three of his children seated inside. Kenosha police have said little about what happened other than that they were responding to a domestic dispute.

On Wednesday, three days after the shooting, state authorities identified the officer who shot Blake as Rusten Sheskey, a seven-year veteran of the Kenosha Police Department. Sheskey shot Blake while holding onto his shirt after officers first unsuccessfully used a Taser, the Wisconsin Justice Department said. State agents later recovered a knife from the driver’s side floorboard of the vehicle, the department said.

The man who said he made the widely circulated cellphone video of Blake’s shooting has said he heard officers yell, “Drop the knife! Drop the knife!” before the gunfire erupted. He said he didn’t see a knife in Blake’s hands.

State authorities did not say Blake threatened anyone with the knife.

On Tuesday, Ben Crump, the lawyer for Blake’s family, said it would “take a miracle” for Blake to walk again. He called for the officer who opened fire to be arrested and for the others involved to lose their jobs. State officials have announced no charges.

Vice President Mike Pence, speaking on the third night of the Republican convention, called for an end to violence in Kenosha and “law and order on the streets of this country for every American of every race and creed and color.” But Pence made no direct mention of Blake or other Black Americans shot or killed by police this year.

Democratic presidential nominee Joe Biden posted a video saying he had spoken with Blake’s parents and other family members.

“What I saw on that video makes me sick,” Biden said. “Once again, a Black man, Jacob Blake, has been shot by the police in broad daylight, with the whole world watching.”

Elsewhere, the Minnesota governor activated the National Guard on Wednesday night to help quell unrest that broke out in downtown Minneapolis following what authorities said was misinformation about the suicide death of a Black homicide suspect. The unrest comes three months after the death of George Floyd under the knee of a Minneapolis police officer touched off a nationwide reckoning over racial injustice.