China-Laos railway's 2nd longest tunnel drilled

File photo taken on Oct. 12, 2017 shows the construction site of the Ban Nakok Tunnel in northern Laos' Oudomxay Province. China Railway Guangzhou Engineering Group (CRECGZ) drilled through the Ban Nakok Tunnel, the second longest tunnel along the China-Laos railway, on Sunday. (CRECGZ/Handout via Xinhua)