BEIJING, Dec 26, 2012 - China launched service Wednesday on the world's longest high-speed rail route, the latest milestone in the country's rapid and - sometimes troubled - super fast rail network.

The opening of the new 2,298-kilometre (1,425-mile) line between Beijing and Guangzhou means passengers will be whisked from the capital to the southern commercial hub in just eight hours, compared with the 22 hours previously required.

China Central Television broadcast the 9:00 am (0100 GMT) departure of the first train live from Beijing West Railway Station. It also carried live reports inside the train showing passengers toting cameras to apparently snap commemorative photos.

Another train departed Guangzhou for the capital at 10:00 am, the official Xinhua news agency reported.

Trains will travel at an average speed of 300 kilometres per hour over the line, which includes 35 stops in major cities such as Zhengzhou, Wuhan on the Yangtze River and Changsha.

State media have reported that December 26 was chosen to start passenger service on the Beijing-Guangzhou line to commemorate the birth in 1893 of revered Chinese leader Mao Zedong.

The Beijing-Guangzhou route was made possible with the completion of a line between Zhengzhou and Beijing. High-speed sections linking Zhengzhou and Wuhan and Wuhan and Guangzhou were already in service.

China's high-speed rail network was established in 2007, but has fast become the world's largest. Xinhua said that China now operates 9,300 kilometres of high-speed railways.

The state-run China Daily newspaper reported Wednesday that the nation's high-speed rail network is set to jump to 50,000 kilometres by 2020, with four main lines running north and south and another four east and west.

The network, while a symbol of China's emergence as the world's second-largest economy, has also been plagued by graft and safety scandals, such as a collision in July 2011 that killed 40 people.

The accident was China's worst rail disaster since 2008 and caused a torrent of public criticism aimed at the government amid accusations that authorities compromised safety in their rush to expand the network.

Authorities said they have taken steps ahead of the new line's opening to improve maintenance and inspection of infrastructure, and emergency response measures.

“The emergency rescue system and all kinds of emergency pre-plans are established to improve emergency response ability,” according to a ministry booklet.

Still, safety concerns remain.

The Global Times newspaper, with close ties to China's ruling Communist Party, on Wednesday quoted a Ministry of Railways official acknowledging continuing problems despite intense efforts to solve them during trial runs.

“We can't make sure it's error-proof in the future, and we have been subject to a lot of pressure from the public,” Zhao Chunlei, deputy chief of the ministry's transportation department, told the paper.

The train's opening means that it will be in service over China's Lunar New Year holiday period, which falls in mid-February next year.

Hundreds of millions of people travel across the country during that period to visit their ancestral hometowns in the world's largest annual migration.