BEIJING, Feb 5 (AP) -- Bonnie Raitt, Sheryl Crow and 10 other musicians are protesting China's decision to sentence a Tibetan music scholar who taught in the United States to 18 years in prison.

In a letter to Vice President Al Gore, who is scheduled to visit China next month, the performers said Ngawang Choephel's case was "a glaring example of the Chinese government's persecution of Tibetan culture."

They asked Gore to visit China only if Ngawang Choephel is released. Their letter, dated Tuesday, was released by the Milarepa Fund, an educational and charitable organization founded by the rock group Beastie Boys. The Associated Press received a faxed copy in Beijing on Wednesday.

The 12 singers said the exiled Tibetan musician, who was visiting his homeland in 1995 to videotape traditional songs and dances, was skilled in playing the dranyan, a six-string lute from Tibet, and was a dancer who had taught music and dance to Tibetan children in exile.

Ngawang Choephel, 30, also was a Fulbright scholar who spent a year at Middlebury College in Vermont studying ethnomusicology the study of the music of a particular region and filmmaking.

A month after he returned to Tibet, Chinese police arrested him and held him for 14 months before announcing the verdict. Government-run Radio Tibet said he confessed to spying for the Dalai Lama.

China condemns the exiled Dalai Lama, Tibet's spiritual leader, claiming he is trying to achieve independence for Tibet. The Dalai Lama has said he wants cultural autonomy for Tibet, not independence.

Also signing the letter to Gore were Michael Stripe, Flea, from the Red Hot Chili Peppers, Tom Petty, Alanis Morissette, Natalie Merchant, Cypress Hill, Rick Rubin, Adam Yauch, Dave Matthews and Ben Harper.