Nine others were injured in the accident on Wednesday night in Shandong province, which occurred as workers were relocating a stretch of track, the state work safety administration said in a statement on its website.

The train had been travelling at 120 kilometres per hour through the city of Weifang at the time of the accident, the state Xinhua news agency said.

State television said a nightly speed limit for trains had been imposed in the area to allow work on the track.

However labourers had started their work just before the limit went into effect, leading to the tragedy.

The workers were employees of China Railway 16th Group, a state-owned construction company that does contract work for the national Railway Ministry.

It was not immediately clear why it took so long for the government to reveal the tragedy.

Chinese businesses and local-level officials often try to cover up industrial and other accidents to avoid punishment.

However, a spokesman for China Railway 16th Group told reporters by phone the company was having difficulty obtaining further information, blaming bad weather at the accident scene.

'We don't have more information than the (government) on the accident at present. It's snowing heavily in the area and traffic and telecommunications are very bad. We have not received an update from the scene,' he said.

The spokesman declined to give his name.

Calls to Shandong provincial railway authorities and the national railway ministry went unanswered. Three area hospitals told reporters by phone they had received no patients from the accident.

The rail line connects Beijing with the port of Qingdao, which will host the sailing competition of the Beijing Olympics in August.

The accident occurred just as the annual Lunar New Year holiday travel rush gained pace.

Millions of Chinese were expected to take buses, trains and planes to gather with their families for China's biggest annual holiday.

The Railway Ministry has forecast a record 178.6 million passengers would travel by rail for the holiday, which officially begins in early February.

State television said the accident did not affect rail traffic.

China's government last week said 101,480 people died in 2007 in more than 500,000 transportation, industrial and other accidents.

It said the number of rail accident deaths fell by 2,595, or 45 percent, but did not provide an absolute figure or otherwise break down the data.

However, the figures suggest the number of train deaths last year was about 3,170.

Labour groups say industrial accidents are vastly under-reported due to cover-ups.

In one of the worst rail accidents in recent times, 126 people were killed and more than 200 injured when two trains collided in central China's Hunan province in 1997. -- AFP