BEIJING » A teenage girl set herself on fire on the grasslands of an ethnic Tibetan region in western China, becoming the eighth child to self-immolate to protest Chinese rule over the region, rights groups said.

Wangchen Kyi, 17, self-immolated and died in China’s western Qinghai province Sunday evening after calling for the long life of the Tibetan people and their exiled spiritual leader, the Dalai Lama, according to the Washington-based International Campaign for Tibet. The group cited reports from exiled Tibetans in contact with people in the area.

Activists say more than 90 people have set themselves on fire in Tibetan areas since February 2009, with an upsurge in recent weeks. The vast majority have been in their late teens and 20s. Activists say the self-immolations show growing desperation over what the protesters see as the marginalization of Tibetan culture and religion under heavy-handed Chinese rule.

China maintains it protects Tibetans’ rights and that the region has enjoyed "leap-frog" economic development in recent decades. Beijing has increasingly sought to crack down on the protests, which it says are inhumane acts instigated from abroad by the Dalai Lama and his supporters to put pressure on the Chinese government.

The Tibetan government-in-exile on Monday reiterated denials of involvement and publicly invited Chinese authorities to send a team to their headquarters in Dharamsala, India, to investigate the allegations.

China accuses the Dalai Lama of wanting to split Tibet off from the rest of China, but he says he seeks real autonomy for Tibetans, not independence.

The Communist Party newspaper People’s Daily said in a commentary today that the Dalai Lama could have prevented self-immolations simply by calling for them to stop, but that he won’t do it.

In an interview in October posted on the Dalai Lama’s website, he said it was difficult to judge whether the method of self-immolation was right or wrong.

"I am quite certain those cases who sacrificed their own life for sincere motivation, for Buddha dharma for wellbeing of the people, from the Buddhist view point, from the religious view point, it is positive," he told NBC. "But if these activities are carried out with full anger, hatred, then wrong. So it is difficult to judge. But anyway it is really very sad, very very sad."

Tibet and surrounding ethnically Tibetan regions have been closed off to most outsiders, and firsthand information from the areas is extremely difficult to obtain.

London-based Free Tibet also reported Sunday’s immolation, which took place in Dokar Mo township in Zeku county, but said the student was 16 and gave a slightly different spelling for her name. Free Tibet said an estimated 3,000 locals attended her cremation service and that she leaves behind her parents and two sisters.

The Zeku county propaganda department today confirmed the self-immolation, but gave no details. Calls to Dokar Mo township’s government and to the county police department rang unanswered.

The International Campaign for Tibet said Wangchen Kyi was a conscientious student and chose to set herself on fire on nomadic grasslands because she feared her body would not be returned to her family if she self-immolated outside a government building in the town.

According to tallies by both rights groups, she is the eighth person under 18 to self-immolate. Four are known to have died, including the youngest, a 15-year-old monk called Dorjee. He set himself on fire last month along with two 16-year-old monks in Aba prefecture in southwestern Sichuan province.

Police in that province announced the arrest over the weekend of a monk and his nephew on accusations of inciting at least eight Tibetans to conduct self-immolation protests, allegedly recruiting them with assurances they would be "heroes" and that they and their families would be "honored" afterward.

Recent Chinese media reports have said that such instigators could be charged with murder, but it was not immediately clear if the monk and his nephew would face those charges. Police in Sichuan declined to comment on the case.

A U.S. statement last week accused Beijing of responding to Tibetan immolations with tightened controls over their freedom of religion, expression and assembly. China’s Foreign Ministry said it had complained to Washington about the comments and said China protects the rights of Tibetan people to maintain their traditional culture and religious freedom.