Stars such as Josh Groban, Akon, Bebe Winans, Phillip Bloch, and Alfre Woodard are speaking out to ET about the shocking footage of Michael Jackson's hair on fire after an accident on the set of a 1984 Pepsi commercial.

"I think in a lot of ways that was a tragic moment for him," Josh Groban tells ET about Jackson's accident. "It's all speculation, but that may have triggered some bad stuff later on."

"That guy was inhuman the kind of giving he was trying to do," Akon adds. "He gave endless and endless and endless amounts of money currency, knowledge, time. He dedicated his whole life to charity. No one can measure a turning point in someone's life. Even after that incident it didn't stop the good things he was doing."

ET joined the celebs at a gala dinner and auction held in honor of Nelson Mandela in NYC on Wednesday night.

"It's been an honor to meet him and become great friends with his family," Bebe Winans says about Mandela. "Every time he opens up his mouth it's always to advance someone else."

Click the video for more from the stars.