Free Tibet says it has identified about 100 accounts carrying false Western names and profile photos.
He had been jailed for sharing information of anti-China protests.
Tibet’s spiritual leader cites the long-running Israeli-Palestinian dispute as an example.
He had called for Tibetan freedom and the Dalai Lama's return.
They had tried to help a truck driver carrying building supplies to a nearby monastery.
Chinese authorities ban gatherings of more than three families and clamp down on communication links in some Tibetan populated areas.
They had opposed excavations deemed harmful to the environment and sacred sites.
They had protested Chinese copper mining on a sacred mountain.
Police drive her quickly to her home to avoid public celebrations of her release.
He must regularly report to authorities and ask permission to travel away from home.
They had written commentaries on deadly protests in 2008 which had angered the Chinese authorities.
He had led a mission to keep order among rival harvesting groups.
Excavations have begun to threaten sacred sites, villagers say.
They also free a monk after he had served three years for opposing Chinese rule.
Villagers had demonstrated against a Chinese gold mining project.
He had served two consecutive terms for activities opposing Chinese rule.
Chinese authorities ban employees' participation in the ancient Buddhist ceremony.
