It added that the body of Lobsang Gyaltsen had been handed over to his family, while Loyak's ashes were given to his relatives.
In April, the Lhasa intermediate people's court had sentenced the two men to death on charges of arson. Under Chinese law, death penalty cases should be reviewed by the Supreme Court, the report said.
"It is impossible to have any confidence that even the most basic legal norms were observed before the Chinese state sanctioned and carried out the killing of these four Tibetans," Stephanie Brigden, director of Free Tibet, said.
Following the surfacing of the execution reports, London-based Tibetan groups called for a vigil outside the Chinese embassy.
Free Tibet said the executions should prompt the British government to rethink the way it engages with China over the region.
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