Tibetan monk and political prisoner Lobsang Darjee died suddenly on November 19 in a Chinese labor camp, according to reports from Radio Free Asia (RFA) and the Tibetan Center for Human Rights and Democracy (TCHRD).

The reform-through-labor camp where Lobsang Darjee, 37, died Tuesday is located on the outskirts of Siling (Chinese: Xining) in Amdo, eastern Tibet (present-day Qinghai), according to RFA.

Darjee had been held at the camp Qinghai since October 2001.

Chinese authorities reportedly told Lobsang Darjee’s family that he had died from a sudden illness.

There is speculation, however, that Darjee’s death was the result of beatings or torture that he may have suffered in prison.

Lobsang Darjee was born on November 19, 1966, in Chuwa in Machen County, Golok Prefecture. When he was 21, he attended Raja Monastery.

On November 15, 1992, during the coronation ceremony for Shingsa Rinpoche, the young abbot of the Raja Monastery, Lobsang Darjee and three other monks put posters advocating Tibetan independence Tibet up on the walls of stores and buildings around the Monastery and raised two Tibetan national flags on the roof of the monastery’s main hall.

Ten days later Lobsang Darjee was arrested by Chinese authorities and was sentenced by the Chinese court of Golok Prefecture to two and an half years in prison and two years’ deprevation of political rights.

Lobsang Darjee was released on May 25, 1995, but he was not allowed to return to the monastery.

To help ensure that the monastary’s young abbot, Shingsa Rinpoche, would have the opportunity to receive a traditional Tibetan Buddhist education, Lobsang Darjee took Shingsa Rinpoche and fled to Dharamsala, India.

He and Shingsa Rinpoche later went to study at Sera Monastery in South India.

In early 2001, Chinese authorities arrested Lobsang Darjee after returned to Tibet to visit his mother.

The Chinese court in Golok Prefecture sentenced Darjee to 15 years in prison and he was sent to the reform-through-labor camp on the outskirts of Siling (Xining) where he died Tuesday.