BEIJING - The second most revered Tibetan Buddhist lama, the Panchen Lama, turned 18 on Wednesday but his whereabouts for the past 13 years is unknown.

The Dalai Lama named Gendun Cheokyi Nyima as Panchen in 1994 but the Chinese government intervened and named their own Panchen a year later. Gendun disappeared and Tibetan sympathizers claim he is being held in house arrest, the BBC reported.

"It's most likely that he's being held somewhere in the vicinity of Beijing itself because that's where the authorities could probably control him the best," Kate Saunders of the International Campaign for Tibet in Washington, told the BBC.

Beijing officials say Gendun is living a free life and the foreign ministry has denied claims of religious persecution in Tibet.