AceShowbiz - Ozzy Osbourne and Yusuf Islam stunned fans at an ironic, star-studded political rally in Washington, D.C. on Saturday, October 30 when they took the stage to perform a surprise show for 200,000 peaceful protesters. American comedians Jon Stewart and Stephen Colbert drew thousands to the U.S. capital as they poked fun at political extremists during the event, which featured a star-studded line-up of stage shows.

Philadelphia collective The Roots kicked off the three-hour demonstration with a 40-minute set, including a jam session with singer John Legend, who joined the band for live renditions of "Dear God 2.0", "Hard Times" and "Little Ghetto Boy" from their collaborative album "Wake Up!".

Soul great Mavis Staples also teamed up with Wilco's Jeff Tweedy for an acoustic version of their collaboration "You Are Not Alone", while rocker Sheryl Crow was accompanied by Kid Rock on the piano for her performance, which featured a video-taped verse from embattled rapper T.I., who was not able to attend the rally.

But the crowd went wild when Islam - formerly known as Cat Stevens - joined Osbourne on stage and surprised the crowd with performances of their respective hits "Peace Train" and "Crazy Train". R&B legends the O' Jays followed-up the performance with a live rendition of their hit "Love Train".

Stewart's closing speech was followed by a brief performance from legendary crooner Tony Bennett, who sang an a cappella version of "America the Beautiful" before the show's performers hit the stage one last time for a group rendition of The Staples Singers' 1972 single "I'll Take You There".