Traffic surged at China’s railway stations, airports and highways on Friday as millions of workers began their journeys back to work after the week-long Lunar New Year holiday.

But many were

delayed with the arrival of another cold front that brought heavy fog.

The China Railway Group said it handled just over 9 million passengers on Friday, 6.9 per cent more than last year as most people travelling home would return to work on Sunday.

READ MORE: Cold snap could delay travellers heading back to jobs after Chinese New Year

The railways carried 7.9 million passengers on Thursday, 4.5 per cent more than last year.

From Friday to Sunday, a strong cold front would sweep southeastward across China, bringing strong winds, rain and snow to the northern, central and eastern regions, the National Meteorological Centre said.

Temperatures would drop by up to 14 degrees Celsius over the three days.

Hundreds of millions of mainlanders returning to their jobs after the holiday also added pressure on air traffic and highways, which was exacerbated by the massive cold front which has brought heavy fog.

More than 100 flights from the northeastern port city of Dalian, Liaoning province, were delayed by thefog as a blue alert was raised for the approaching cold front, China News Service reported.

The temperature in Dalian dropped to minus 4 degrees, and would dip further to minus 8 degrees on Saturday, the city’s meteorological department said.

Several thousand travellers were stranded when fog cut visibility on highways, the report added.

Travellers in Shanghai and Zhejiang province were also affected by poor visibility which prompted the authorities to close some highways or cut speed limits to between 60 and 80km/h. Visibility in Shanghai’s Minhang, Songjiang, Fengxian and Jinshang districts was down to just 200m.

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Beijing’s traffic management bureau expected the return of travellers to peak on Friday and Saturday, putting more pressure on highways, flights and railways.

The bureau said traffic congestion was likely around Beijing and Beijing West railway stations, the Beijing Capital International Airport and bus terminals.

Friday was the fifth day of the Lunar New Year, commonly known as powu when many taboos can be broken. Many mainlanders will celebrate by lighting fireworks, which will only raise the pollution levels in the capital.

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