A popular advocate of Tibet’s traditional culture and language is believed to have been detained by Chinese authorities, as another Tibetan self-immolated in protest against Chinese rule.One source, calling from inside Tibet, told that Dawa Dorje, who works as a government researcher in Nagchu prefecture in the Tibet Autonomous Region (TAR), was detained last week after expressing concern over the closure of Tibetan monasteries.He was picked up at Tibet's capital Lhasa's Gonggar Airport, the source said, speaking on condition of anonymity."There is hardly anyone in Nagchu who doesn't know about this young Tibetan Dawa Dorje," the source said. Dorje's age is not known."He was detained at Gonggar Airport. He was arrested and taken away but details are not known. His family members could not locate him and are desperately trying to find out where he has been detained," the source said.