"The monk, identified as Ngawang Gyaltsen, a 41-year-old Tibetan artist, was secretly arrested by Chinese police under the cover of night from his house on February 24," Mr Ngawang Tharpa told the Tibet Post International (TPI) on Monday afternoon.
"Local Tibetans suspect he was detained because of suspected involvement in political activities challenging Beijing's repressive rule," the source said.
"local Tibetans are worried and tense because they have no information about him," the source said, speaking on condition of anonymity.
"It was later found out that Gyaltsen was taken into custody by Chinese security in Nagchu County after his disappearance," Mr Tharpa added.
According to the source, Gyaltsen was forced to leave the monastery after the "Patriotic re-education" campaigns, in which Chinese authorities forced monks and nuns to denounce His Holiness the Dalai Lama, and study materials praising China's leadership.
"After leaving his monastery, Ven Gyaltsen could not travel and meet with his family and friends without government authorization and he was kept under strict police surveillance," the source said.
Gyaltsen is a native of Nagchu County in Central Tibet Tibet (the Nagqu Prefecture of the Tibet Autonomous Region). He was a monk at Shag Rongpo Monastery where he studied and became a well-known artist.
The Chinese regime has imposed severe restrictions on internet and phone connections by increasing a wider crackdown on communications across Tibet in an attempt to prevent any news reaching the outside world.
In Tibet today, Tibetans are being arbitrarily arrested, imprisoned and tortured for merely expressing their suffering under Chinese rule. However, authorities in Beijing still claim that "China 'peacefully liberated' Tibet, and that the "Tibetans are living in a Maoist socialist paradise."