Staff members check the wall of Yindongpo Tunnel of Guizhou-Guangxi Railway with the light from torches in Duyun City, southwest China's Guizhou Province, Aug. 20, 2018. (Photos: Xinhua)

Railway maintenance workers here patrolled the 8.5-kilometer tunnel and took necessary measures to ensure the safety of railway transportation during the flood season.

Staff members climb down a stone wall while patrolling the Yindongpo Tunnel of Guizhou-Guangxi Railway in Duyun City, southwest China's Guizhou Province, Aug. 20, 2018.

Railway maintenance workers here patrolled the 8.5-kilometer tunnel and took necessary measures to ensure the safety of railway transportation during the flood season.

Staff members walk in the Yindongpo Tunnel of Guizhou-Guangxi Railway for a patrol in Duyun City, southwest China's Guizhou Province, Aug. 20, 2018.

Railway maintenance workers here patrolled the 8.5-kilometer tunnel and took necessary measures to ensure the safety of railway transportation during the flood season.

Staff members check the wall of Yindongpo Tunnel of Guizhou-Guangxi Railway with the light from torches in Duyun City, southwest China's Guizhou Province, Aug. 20, 2018.

Railway maintenance workers here patrolled the 8.5-kilometer tunnel and took necessary measures to ensure the safety of railway transportation during the flood season.

Railway maintenance workers here patrolled the 8.5-kilometer tunnel and took necessary measures to ensure the safety of railway transportation during the flood season.

Staff members eat lunch in front of the Yindongpo Tunnel of Guizhou-Guangxi Railway in Duyun City, southwest China's Guizhou Province, Aug. 20, 2018.