Lhundup was formerly employed as an official in the municipal administration of Lhasa, where he served for several years prior to his arrest in 1988 on allegations of involvement in underground political activities. He was detained for ten months at Gutsa Detention Centre without due process of law and was never formally charged or brought before a court. Ultimately, he was released after the authorities failed to produce any evidence to substantiate the allegations against him.

Following his release, Lhundup worked in a small shop while remaining under constant surveillance by the security apparatus. Aware that his movements and activities were being closely monitored by the secret police, and fearing further arbitrary detention, he fled Tibet in the summer of 1993. He subsequently reached Dharamsala, where he sought refuge in exile.