Beijing - Brutal winter weather across China on Monday stranded hundreds of thousands of people and choked energy flows, claiming a rising human and economic toll that pummeled local stock prices ahead of Chinese New Year.

At least 24 people had died in two weeks of accidents due to snow, sleet and freezing cold across central, eastern and southern China, regions used to milder winters, Xinhua news agency said.

Many highways, railways and airports were paralyzed, especially in the east, with officials in Hunan, Jiangsu and other provinces calling the snow and cold the worst in decades.

The bad weather has hit as tens of millions of Chinese head home to celebrate the Lunar New Year, starting on February 7 this year, a huge human tide that strains trains and planes at the best of times.

China also counted the economic cost from stalled production and shipping and the power brownouts across more than half the nation's 31 provinces. The main Shanghai stock index plunged 7.19 percent, its fourth biggest drop this decade, as investors added the weather woes to gloom about inflation and the global economy.

"This is like another SARS outbreak, which temporarily blocks bloodflow in the economy and causes short-term pain," said Gu Lingyun, fund manager at Orient Securities, referring to the epidemic that panicked China in 2003.

"The snow also calls into question whether the government can successfully tame inflation."

The winter chaos comes at a time when China is anxious to show the outside world its transport network and infrastructure are up to the task of hosting the summer Olympics in August.

TRAIN HAVOC

For millions of Chinese workers, the pressing worry is making it back to hometowns and villages for the Lunar New Year celebrations.

Flights at dozens of regional airports have been reduced to a snail's pace or stopped completely. Icebound highways throughout central and eastern provinces have been closed.

At the main rail station in Guangzhou, in the relatively warm commercial far south, 170,000 people crammed together waiting for trains that cannot leave because of electric trains stranded down the line, Xinhua reported.

By the end of Monday, a backlog of 600,000 waiting for trains from the city was expected. Television showed green-uniformed anti-riot troops ready to keep order around the station.

"I've been here in Guangzhou for close to 10 years and have never seen anything like this before," said Song Zhigang, waiting for a train to Wuhan in central China.

"What happens at night when the temperature goes down? For us adults it's no problem, but what about the children?" he told Reuters, his breathe frosting the chilly air.

The China Meteorological Administration said the cold snap showed no signs of lifting and issued a "red alert" warning of snow storms in some central and eastern areas, including around Shanghai, the nation's commercial hub.

"Cut unnecessary outdoors activities," urged the notice on the central forecast Web site (http://www.nmc.gov.cn).

Cargo ships docked at Shanghai's Baoshan Port were also delayed by snow that has hampered operations.

PRICE OF WILD WEATHER

Already the country is guessing the economic cost, especially from coal shipment delays that have intensified power shortfalls.

The country's power shortage amounts to 39.9 gigawatts -- some 5.6 percent of total generating capacity -- with brownouts worst in the country's central and southwest, Zhu Hongren of the National Development and Reform Commission, said.

The power outages have forced some Chinese metal producers to halt or cut output.

"Bad weather hit coal transportation. Hydropower in the south was severely affected by the worst drought in five decades," Zhu told a news conference. He also blamed closure of small mines.

The Ministry of Civil Affairs, which handles disaster relief, estimated direct economic losses so far at 18.2 billion yuan ($2.5 billion), according to state television.

Residents in central and southwest China are also complaining of shortages of fresh foods and rocketing prices for rice, vegetables and eggs.

"A lot of transport has stopped, so vegetables and what-have-you can't be brought in," Xu Jinyun, a resident of Lujiang in snow-bound Anhui province in east China told Reuters.

The government has not announced deaths due to freezing in homes. But homes south of the Yangtze River generally do not receive central heating and are not built for such icy weather.
(Additional reporting by Ben Blanchard in Beijing, George Chen in Shanghai, and John Ruwitch in Guangzhou; Editing by Nick Macfie and Alex Richardson)