Ngawang Gyaltsen, a monk of Drepung Monastery, was approximately 32–33 years old at the time of his arrest. He played a leading role in the 1988 demonstrations in Lhasa, which were organized in protest against the imposition of martial law by the Chinese authorities. Together with other monks, he was involved in distributing leaflets and posting wall posters in preparation for the demonstrations.

A few days before the protests took place, Ngawang Gyaltsen attempted to escape to India with several fellow monks but was arrested in Lhasa before he could leave Tibet. In November 1989, he was sentenced to 17 years’ imprisonment. He was tried as part of a group of ten Drepung monks accused of “reactionary activities” and “espionage.”

Ngawang Gyaltsen was imprisoned in Drapchi Reform Through Labour Prison, where he was reportedly assigned to work in the vegetable garden. A former political prisoner reported seeing him there on 25 August 1992. Originally from the rural area of Toelung Dechen, northwest of Lhasa, his family continues to reside there.