Late singer Michael Jackson had once hid in a secret underground tunnel at a concert to avoid talking to his staff, says his voice coach.
Coach Yvie Burnett, who tutored Leona Lewis when she won Britain's The X Factor in 2006, worked with the Thriller hitmaker during a tour - and insists she was stunned by his "rude" behaviour, reports contactmusic.com.
"I remember a long time ago, I was working with Michael Jackson and he had a tunnel built which took him from the stage into the dressing room. He crawled into this big white tunnel so he didn't have to speak to any of us," she said.
"He was probably the rudest (celebrity) because we all went up to meet him and he wouldn't speak to anyone, not even the crew who were beside him," she added.