A 17-year-old chess grandmaster was arrested following an alleged violent outburst that led to him being expelled from his national championship.

Christopher Yoo was arrested by the police in the US city of St Louis after he allegedly struck a female videographer following a defeat in the United States Chess Championship.

Yoo had been defeated by American chess great Fabiano Caruana, leaving the teenager with just one point from his opening five games.

He then is alleged to have struck the videographer while exiting the playing hall.

The US Chess Federation said Yoo was arrested and charged with fourth-degree assault, before being released back to his parents. 

The federation said Yoo will be handled by the juvenile justice system in Missouri.

In a statement released by his parents, Yoo said there was no excuse for his actions.

"I am really sorry for hitting the videographer. I was disappointed losing the game to Caruana and lost my temper. That's no excuse, I know," he wrote.

"I am really sorry for what I did. It was a serious mistake. Every day I wish I could go back in time and undo it, but I can't. I am very sad for what I did and I hope the videographer is OK."

The tournament's chief arbiter Chris Bird expelled the teenager from the tournament, annulled the results of his previous games, and issued a bye to all players slated to face Yoo for the remainder of the event.

"We take player conduct seriously and do not tolerate violations of our standards," a statement from the St Louis Chess Club, the host of the event, read.

"We acted swiftly to address this situation, ensuring a respectful and safe environment for everyone involved in the tournament."

Yoo earned his spot in the tournament after winning the US Junior Chess Championship earlier in the year.

He was a chess prodigy from a young age, becoming an American master in 2016 at the age of nine and an international master at the age of 12.

The US Chess Championships and chess in the city of St Louis are not strangers to controversial moments. 

Hans Niemann was accused of cheating by Magnus Carlsen at the Sinquefield Cup in 2022.

In that same year, Sam Sevian snapped the king of his opponent — again Niemann — during a game in the US Chess Championship.