Fresh concerns have been raised over the way in which The X Factor treats its contestants after it was revealed that teenager Luke Lucas had a “meltdown” during the judges’ houses stage of the show.

According to The Sun the 16-year-old – who appeared chirpy and confident at auditions – broke down after stumbling over his final song in front of Gary Barlow and Robbie Williams.

The dramatic scenes will be seen in Saturday’s edition of the show in which the 32 finalists travel to the judges’ houses to compete for a place in the live shows.

“He found the pressure really difficult,” an insider told the paper.

“He messed up one of his songs then started crying when he feared he had blown his chance. Gary and Robbie were really worried.”

Luke’s experience is similar to that of 2010 finalist Cher Lloyd, who also broke down at Cheryl Cole’s house after forgetting the words to her song.

However Cheryl eventually put her through to the finals, where she went on to finish fourth.

The latest drama comes hot on the heels of the controversy over the treatment of serial auditioner Ceri Rees, who was allegedly ridiculed by Gary Barlow after being invited by producers to audition for the fourth time.

Marjorie Wallace of the mental health charity Sane has hit out at the show, telling the Sun she was unhappy with the treatment of contestants.

“It’s like ‘conditioning experiments’ that took place in the Sixties on animals,” she said. “Producers need to take responsibility for potential consequences.”