Kirti monk Lobsang Tsultrim called out for Tibetan freedom before being taken away by police.
Tsawa Danyuk had offended both Chinese authorities and Tibet's Buddhist clergy with his critical writings, sources say.
He was convicted on unknown charges after warnings of self-immolation protests circulated in Serthar.
He will be jailed again if he sings politically sensitive, 'illegal' songs, he is told.
Seized by police for calling out in public for Tibetan freedom, Sonam Tashi has vanished in custody.
Chinese visitors to Kumbum jump the queue ahead of Tibetans, while paramilitary police monitor the crowds at an annual gathering.
They are being stopped at Gansu's border with Sichuan and told to abandon their cars, sources say.
The blaze kills wildlife and livestock but results in no human casualties, a local source says.
Amchok Phuljung had recorded popular songs praising the Dalai Lama and Tibet's exile prime minister.