DALLAS (AP) — A Dallas school district is investigating a high school English teacher who asked students to write about a modern-day hero and listed the 17-year-old accused of killing two people during Wisconsin protests as one possible option.

Kyle Rittenhouse has been accused of fatally shooting two people and wounding another in Kenosha following the police shooting of Jacob Blake.

The writing assignment also listed Joseph Rosenbaum, one of the protesters Rittenhouse is accused of killing; along with Mahatma Gandhi, César Chávez, Malcolm X, and George Floyd.

Rittenhouse, a white teen who was armed with a semi-automatic rifle as he walked Kenosha’s streets with other armed civilians during August’s protests, would face a mandatory life sentence if convicted of first-degree intentional homicide. Under Wisconsin law, anyone 17 or older is treated as an adult in the criminal justice system.

He was taken into custody on Wednesday in Antioch, Illinois, the city about 15 miles (24 kilometers) from Kenosha where he lives.

The shootings were largely caught on cellphone video and posted online. The shooting by police of Jacob Blake, a 29-year-old Black man who was left paralyzed from the waist down, was also caught on cellphone video. That shooting made Kenosha a focal point in the fight against racial injustice that has gripped the country since the May 25 death of George Floyd in Minneapolis police custody.

Three nights later, Rittenhouse was armed and on the streets of Kenosha, saying that he was protecting businesses from protesters, according to widely circulating cellphone footage.

The criminal complaint said that Joseph Rosenbaum, 36, of Kenosha, following Rittenhouse into a used car lot, where he threw a plastic bag at the gunman and attempted to take the weapon from him. The medical examiner found that Rosenbaum was shot in the groin and back — which fractured his pelvis and perforated his right lung and liver — and his left hand. He also suffered a superficial wound to his left thigh and a graze wound to his forehead.

Rittenhouse then ran down the street and was chased by several people shouting that he just shot someone before he tripped and fell, according to the complaint and video footage. Anthony Huber, 26, of Silver Lake, was shot in the chest after apparently trying to wrest the gun from Rittenhouse, the complaint said.

Gaige Grosskreutz, 26, who appeared to be holding a gun, was then shot in the left arm after approaching Rittenhouse, the complaint said.

Another Rittenhouse attorney, Lin Wood, said the teenager was acting in self-defense.

“From my standpoint, it’s important that the message be clear to other Americans who are attacked that there will be legal resources available in the event false charges are brought against them,” he said. “Americans should never be deterred from exercising their right of self-defense.”

Kenosha police faced questions about their interactions with the gunman on Tuesday night. 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 yelled for him to be arrested because he had shot people.

Kenosha County Sheriff David Beth said the gunman likely slipped away because the scene was chaotic, with lots of radio traffic and people screaming, chanting and running — conditions he said can cause “tunnel vision” among law officers.

Video taken before the shooting shows police tossing bottled water from an armored vehicle and thanking civilians armed with long guns walking the streets. One of them appears to be Rittenhouse.

Wisconsin Lt. Gov. Mandela Barnes decried how Rittenhouse, whom he described as a vigilante accountable to nobody, could walk away while police talked about finding a knife inside Blake’s vehicle after he was shot in the back.

He said the fact that Rittenhouse and others came to Kenosha to take matters into their own hands “was completely horrifying.”