The United States says it is "seriously concerned" that more Tibetans have set themselves on fire in China, and says the actions represent deep frustration with Chinese government restrictions.
U.S. State Department spokeswoman Victoria Nuland said Monday the self-immolations show there is enormous anger over severe Chinese restrictions on human rights and religious freedoms.
She added that Washington has consistently raised the issue with China.
Reports from Tibet say another Tibetan monk died Sunday after setting himself on fire in Dari county of Amdo region.
The reports say that before 42-year-old Lama Sopa Tulku set himself ablaze, he said he was doing so to commemorate all the Tibetans who have died since 2009 for Tibet's freedom and for the return of their spiritual leader, the Dalai Lama, who fled to India in 1959 amid an abortive uprising against Chinese rule.
Two other Tibetans immolated themselves Friday near the flashpoint Kirti monastery in Sichuan province.
At least 15 Tibetan Buddhists are believed to have set themselves on fire in the past year since a young monk protesting Chinese rule died after self-immolating outside the Kirti monastery in March. That death sparked months of protests by monks and nuns and triggered a major Chinese crackdown that included the arrests and disappearances of hundreds of monks.
Beijing has denounced the self-immolations and accuses Tibetan exiles of encouraging them. The government says Tibetans enjoy religious freedom.