The much-vaunted Wuhan-Guangzhou high-speed railway was bought to a standstill by a smoker within a week of its opening last month.

A passenger set off an alarm while smoking a cigarette, and officials spent the next two-and-a-half hours in a fruitless search of the train for the culprit. This is almost as long as the train takes to cover the entire 1,100km journey.

The train was in Guangzhou railway station when it was delayed and had not yet begun its 350kph journey, Xinhua reported.

"Smoking is strictly forbidden on the Wuhan-Guangzhou high-speed train, even in the toilet," a spokesman with Guangzhou Railway Group Corporation was quoted as saying.

China plans to build more high-speed lines, including one that will connect Chengdu with Chongqing. Construction of this 310km line will begin in 2010.