Traffic on the world's longest high-speed railway resumed Friday afternoon after a massive water leak delayed more than 20 trains, Chinese railway authorities said.

The leak was discovered around noon in a tunnel along the Beijing-Guangzhou high-speed railway, according to a statement issued by the Wuhan Railway Bureau. The tunnel connects the cities of Changsha and Miluo in central China's Hunan Province.

Traffic returned to normal from 2:30 p.m. after workers attended to the leak, it said.

The Beijing-Guangzhou line, which links the Chinese capital and the southern metropolis of Guangzhou over a total distance of 2,298 km, went into operation on Dec. 26, 2012.