Photo taken on April 26, 2019 shows yaks roaming at the foot of the Mount Shishapangma in Nyalam County of Xigaze, southwest China's Tibet Autonomous Region. (Xinhua/Jigme Dorjie)

Two foreign tourists take selfies near the Mount Shishapangma in Nyalam County of Xigaze, southwest China's Tibet Autonomous Region, April 26, 2019. (Xinhua/Jigme Dorjie)

Photo taken on April 26, 2019 shows yaks roaming at the foot of the Mount Shishapangma in Nyalam County of Xigaze, southwest China's Tibet Autonomous Region. (Xinhua/Jigme Dorjie)

A tourist takes a photo of the Mount Shishapangma in Nyalam County of Xigaze, southwest China's Tibet Autonomous Region, April 26, 2019. (Xinhua/Jigme Dorjie)

Photo taken on April 26, 2019 shows the Mount Shishapangma in Nyalam County of Xigaze, southwest China's Tibet Autonomous Region. (Xinhua/Jigme Dorjie)

Photo taken on April 26, 2019 shows the Peiku Lake near the Mount Shishapangma in Nyalam County of Xigaze, southwest China's Tibet Autonomous Region. (Xinhua/Jigme Dorjie)