Tibetan sources say a 17-year-old girl set herself on fire Sunday to protest Chinese rule in ethnic Tibetan areas.
Witnesses say Wanchen Kyi shouted slogans in support of the Dalai Lama and a free Tibet as she was engulfed in flames. She died at the scene.
More than 3,000 Tibetans and monks later gathered at the site of the self-immolation protest and recited prayers.
A day earlier, two young monks also died after setting themselves on fire to protest Chinese rule.
Ninety-five Tibetans have now self-immolated in western China since 2009, with 28 cases reported in November alone. The acceleration of self-immolations has coincided with Tibetans staging several anti-China rallies, despite a heavy Chinese security presence.
On Sunday, Chinese state media quoted police in Sichuan province as saying a detained Tibetan monk and his nephew had confessed they incited eight people to set themselves on fire in anti-Chinese protests. Three people died in the self-immolations.
According to the police, the men say they were acting on the orders of Tibet's exiled spiritual leader, the Dalai Lama.
Beijing accuses the India-based Dalai Lama of inciting the self-immolations to promote Tibetan separatism, a charge he denies.