The Shanghai-Kunming railway line in southwest China's Guizhou Province resumed operation late on Thursday after a period of closure forced by a gasoline leak near the line on Wednesday, the local railway bureau said.

About 2,000 tonnes of gasoline escaped from a broken pipe after an accident at a high-speed railway construction site in Pingba County of Anshun City, according to rescuers.

The leak started at about 12:40 a.m. on Wednesday following the collapse late on Thursday of a construction tower at the site.

The leak caused delays and cancellations to trains traveling from Kunming station to Beijing, Shanghai, Nanjing, Jinan, Chongqing and Guilin via the Kunming-Shanghai line.

Oil supply resumed after a new pipe was successfully welded at the leak site at 6:30 p.m. on Thursday.

The Shanghai-Kunming railway line's Guizhou section resumed operation at 8 p.m. and the first cargo train passed the site at around 8:24 p.m.

The pipe belongs to a branch of Sinopec, the country's largest oil refiner.

The cause of the accident is under investigation.