The young male was caught hiding blank 'wild card' tiles that he could have used to score extra points, reports the Daily Mail.
He was quickly marched out of the prestigious tournament held in Orlando, Florida. The winner of the five-day event receives £6,380.
Officials from the National Scrabble Association refused to reveal the identity of the competitor due to his age.
This is the first instance of cheating in Scrabble at a national level and the incident has caused controversy at the tournament and has spread online.
Executive director of the National Scrabble Association John D. Williams commented on its unusual nature, saying: "There is usually 'good self-policing' in the Scrabble world."
Scrabble All-Star champion David Gibson, 61, from Spartanburg, South Carolina is currently leading the 350-player event.
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