The United States said Wednesday it has raised concerns about human rights in Tibet with China as it renewed its call on Beijing to address its policies amid a wave of self-immolations by monks.

Asked if the United States has brought up the issue of the Tibetan protests with Beijing, the US State Department said without details, "Yes, we have, and we remain seriously concerned."

"These acts clearly represent anger and frustration with regard to Tibetan human rights, including religious freedom, inside China," the State Department said in a written response to a question.

"We urge Chinese leaders to address counterproductive policies in Tibetan areas that have created tensions; and to protect Tibet's unique religious, cultural and linguistic identity," it said.

A Buddhist nun who burned herself to death this week became the first woman and the ninth Tibetan to set fire to themselves in southwest China in recent months. Tibetan exiles say that five have died.

China blamed Tibet's exiled spiritual leader, the Dalai Lama, calling the self-immolations "terrorism in disguise." The Nobel Peace laureate advocates non-violence and in the past has criticized such deadly protests.

The Tibetan government-in-exile based in India says that it does not encourage self-immolations but understands the frustrations behind them. Thousands of Tibetans in India have attended protests or prayers to criticize China's rule of the predominantly Buddhist region.

The Dalai Lama fled Tibet for safety in India in 1959. He met in July with US President Barack Obama, angering China.