A video of a group of mostly white teen boys taunting a Native American man during the Indigenous Peoples March in Washington, DC went viral Saturday, prompting widespread criticism of the youths.

The images show a throng of boys, many wearing Make America Great Again hats, surrounding the man as he beat a drum and sang a song. One boy is also seen standing and smirking close to the man.

He was identified by The Washington Post as 64-year-old Nathan Phillips, an indigenous activist who fought in the Vietnam War.

He told the paper that he felt threatened by the teens.

“It was getting ugly, and I was thinking: ‘I’ve got to find myself an exit out of this situation and finish my song at the Lincoln Memorial,’” Phillips said. “I started going that way, and that guy in the hat stood in my way and we were at an impasse.”

The Indigenous Peoples Movement, which organized the march, slammed the teens, saying what happened validated the need for their march.

Some members of the crowd were wearing clothing from Covington Catholic High School in Kentucky, which reportedly sent students to Washington to take part in Friday’s anti-abortion March for Life event.

The school and the Diocese of Covington issued a joint statement to the Cincinnati Enquirer on Saturday that directly apologized to Phillips.