Lhase Sonam, an exiled Tibetan based in Switzerland, reported that in spite of repeated attempts by his family to track him down, no news of Jampa Wangchuk's whereabouts has been reported since he was handed his sentence and stripped of his political rights at the Lhasa Intermediate People's Court in June.
Jampa, from Tsothod, Phenpo Lhundhup county, near Lhasa, was arrested in April 2008, a month after 350 monks from Drepung monastery, at which he taught Buddhist scripture and had recently been appointed Gaku, meaning he was responsible for laying down the rules, staged a peaceful rally protesting Beijing's hosting of the 2008 Olympic Games.
The monks are reported to have begun walking from the monastery, located on the outskirts of Lhasa, to Bharkor Street, an important landmark in the Tibetan capital, before they were stopped by Chinese police en route.
Hundreds of monks were subsequently arrested and subjected to torture, and the ancient university monastery was blockaded by Chinese military, who are reported to have forced many monks to leave the monastery and launched a compulsory patriotic reeducation campaign for those that remained.
It is believed that prior to the protest, Jampa, who joined Drepung in 1982, refused a request from the Chinese authorities to prevent the monks at Tibet's largest monastery from joining the wave of protests spreading across Tibet.
He was later arrested on charges of corruption.
Many of the arrested monks are believed to be imprisoned in Nyari prison in Tibet's second city, Shigatse, and in Chushul prison near Lhasa.
Lhase Sonam also reported that fellow monk Ngawang Choenyi, 42, from Sharsarsul, Lhasa, who was arrested on the same day, has received a seven year prison sentence.