Scores of people were arrested in a traditionally Tibetan area of western China following public calls for the return of Tibet's exiled spiritual leader, the Dalai Lama, reports said Friday.

Also Friday, China moved to tighten its control over Tibetan Buddhism by asserting the communist government's sole right to recognize Buddhist reincarnations of the lamas that form the backbone of the religion's clergy.

All future incarnations of living Buddhas related to Tibetan Buddhism "must get government approval," the official Xinhua News Agency said, citing the State Administration for Religious Affairs.

Reincarnate lamas, known as tulkus, often lead religious communities and oversee the training of monks, giving them enormous influence over religious life in Tibet.

Police and army reinforcements were sent to the town of Lithang in western Sichuan province following the incident Wednesday at an annual horse festival that attracts thousands, according to the overseas monitoring group International Campaign for Tibet and the U.S. government-supported Radio Free Asia.

The reports said a local man, Runggye Adak, was detained after he climbed onto a stage erected for Chinese officials, grabbed a microphone and asked the crowd if they wanted the Dalai Lama to return. Hundreds responded with a roaring yes, the reports said.

A crowd later gathered a detention center to appeal for Runggye Adak's release, but officers fired warning shots to disperse the group, it said.

RFA said about 200 Tibetans were detained following the protest, but gave no indication of whether they were still in custody.

A woman who answered the telephone at Lithang's police station confirmed the protest had occurred, but hung up when asked for details.

The Dalai Lama fled Tibet for India in 1959 amid a failed uprising against Chinese rule. Tibetans remain strongly loyal to the Buddhist leader, despite persistent efforts to demonize him by Chinese authorities.

China claims Tibet has been its territory for centuries, but many Tibetans say they were self-ruled for most of that period.

On the living Buddhas issue, China already insists that only the government can approve the appointments of the best known reincarnates, including the Dalai and Panchen Lamas, the No. 1 and No. 2 figures in Tibetan Buddhism.

A copy of the new rules posted to the administration's Web site said that the selection of reincarnates "must preserve national unity and solidarity of all ethnic groups."

"The process cannot be influenced by any group or individual from outside the country," it said in an apparent reference to the Dalai Lama and supporters.

Reports said Runggye Adak's outburst came amid Chinese celebrations of the 80th anniversary of the founding of the People's Liberation Army, which in 1950 marched through the Lithang area on its way to occupying the entire region.

Runggye Adak, 52, also called for the release of 18-year-old Gendun Choekyi Nyima, picked by the Dalai Lama in 1995 as the reincarnation of the Panchen Lama, Tibet's second-highest leader, RFA said. The boy disappeared soon afterward and has reportedly been in Chinese custody since. China says he is living a normal life but has given no details.

Having rejected the Dalai Lama's choice, Beijing installed Gyaltsen Norbu, 16, as the 11th Panchen Lama in 1995.

The International Campaign for Tibet said calls were also made for the release of Tenzin Deleg Rinpoche, a senior lama who attracted thousands of followers before authorities sentenced him to life in prison in 2002 for allegedly promoting Tibetan independence and involvement in bombings that killed one person.