A Tibetan filmmaker has fled to the United States from China to escape the authorities’ harassment, after being held incommunicado, imprisoned and subjected to deprivation of political rights over the last ten years.

Dhondup Wangchen, 43, left the Tibetan-populated area in Qinghai province and arrived in San Fransisco on Monday, joining his family after more than ten years of separation. His wife Lhamo Tso had been campaigning for his release.

Dhondup Wangchen (middle) is reunited with his family in the US. Photo: Filming for Tibet.

“After many years, this is the first time I’m enjoying the feeling of safety and freedom,” he said in a statement issued Wednesday by Filming for Tibet, an NGO founded by his cousin to support the work of Tibetan filmmakers.

“I would like to thank everyone who made it possible for me to hold my wife and children in my arms again. However, I also feel the pain of having left behind my country, Tibet.”

Considered one of the most prominent Tibetan political prisoners, Wangchen has worked to raise awareness about the denial of fundamental rights of Tibetans such as the right to freedom of expression, according to the Washington-based International Campaign for Tibet.

Wangchen is known for his documentary Leaving Fear Behind, based on interviews with ordinary Tibetans in China between 2007 and 2008. In the film, the interviewees spoke about their views on the Dalai Lama and their criticism of China’s policies in Tibetan-populated areas.

The filmmaker was taken into custody in March 2008, but the footage was smuggled to Switzerland where Filming for Tibet edited it into a 25-minute film. It was first screened to foreign journalists in Beijing, two days before the opening ceremony of the 2008 Beijing Olympics.

Wangchen was held incommunicado for over a year during his detention. In December 2009, he was given a six-year jail term in a secret trial for “inciting subversion of state power.”

NGO Amnesty International said he was “tortured and otherwise ill-treated, held for about six months in solitary confinement, and denied medical treatment” during his detention and imprisonment.

After being released from prison in 2014, Wangchen returned to his home village in Gansu province to serve his three-year sentence of deprivation of political rights. That sentence expired in June this year.

Amnesty called the Tibetan filmmaker “a prisoner of conscience during his incarceration, imprisoned solely for the peaceful exercise of his right to freedom of expression.”

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International Campaign for Tibet President Matteo Mecacci said Wednesday: “The six years Dhondup Wangchen had to spend in jail are a stark reminder of the human costs that China’s policies continue to have on the Tibetan people. Dhondup Wangchen should have never had to pay such a high personal price for exercising his freedom of expression.”

Wangchen’s arrival in San Francisco was welcomed by human rights groups and US House Minority Leader Nancy Pelosi.

Human rights groups have long criticised the Chinese government for using the broad charges of “separatism” and “subversion” to target ethnic minorities such as Tibetans and Uyghurs.

China has rejected accusations from exiles and rights groups of human rights abuses against its ethnic minorities.