By . Associated Press Reporter . PUBLISHED: . 16:31 EST, 30 January 2013 . | . UPDATED: . 02:31 EST, 31 January 2013 . Thick smog in China forced airlines to cancel flights, as factories in Beijing were temporarily shut down to ease the pollution. Street lamps and the outlines of buildings were barely visible in the Chinese capital, as pedestrians donned face masks to guard against the smog which has blighted parts of the country for a fortnight. The flight cancellations stranded passengers during the first week of the country's busiest period of  travel, due to the Chinese New Year on February 10. Scroll down for video . Smog: The Central TV Tower in Beijing is barely visible after a fourth day of heavy smog . Safety measure: Officials in Beijing told 103 heavy polluting factories to cease operations in an attempt to reduce smog levels . More than 100 flights were canceled in the eastern city of Zhengzhou, 33 in Beijing, 20 in Qingdao and 13 in Jinan. The US Embassy reported an levels of PM2.5 - tiny matter that can penetrate deep into the lungs - was more than 20 times higher than World Health Organization safety levels over a 24-hour period. Liu Peng, an employee at a financial institution in Beijing, said he will keep his newborn baby indoors. He said: 'It's really bad for your health, obviously. I bike to work every day and always wear a mask. The pollution in recent years is probably due to the increase in private cars and government cars.' Visibility was less than 100 meters in some areas of eastern China, the official Xinhua News Agency reported. Every year, China's transport system bursts at the seams as tens of millions of people travel for the Lunar New Year holiday, in the world's largest seasonal migration of people. Invisible: Thick smog blankets buildings in Beijing last week, a city that has long had pollution problems . Reduction: Officials in Beijing government departments and state-owned enterprises to reduce their use of cars by a third . Ren Haiqiang, a bank worker said he had booked tickets to fly out of Beijing on Thursday to visit family in the coastal city of Dalian, but was now worried about flight cancellations. 'Traveling over the holiday is already a huge hassle, along with all the gift-giving and family visits. 'We thought flying would be the best way to avoid the crush, but if the weather continues like this we'll be in real trouble,' he said. Beijing's city government ordered 103 heavily polluting factories to suspend production and told government departments and state-owned enterprises to reduce their use of cars by a third, Xinhua said. The measures last until Thursday. Beijing's official readings marked the smog as at a 'severe' level and prompted the city government to advise residents to stay indoors. indoors: Women wearing masks doing their morning exercises in Beijing, China as people were warned to stay indoors as much as possible . Lasting: The government said that because there was no wind, the smog would not dissipate quickly . The government said that because there was no wind, the smog would not dissipate quickly. Patients seeking treatment for respiratory ailments rose by about 30 per cent over the past month at the Jiangong Hospital in downtown Beijing, Emergency Department chief Cui Qifeng said. 'People tend to catch colds or suffer from lung infections during the days with heavily polluted air,' he said. Air pollution has long been a problem in Beijing, with the city hitting its highest reading on January 12. Hospitalised: Patients seeking treatment for respiratory ailments rose by about 30 per cent over the past month at the Jiangong Hospital in downtown Beijing, Emergency Department chief Cui Qifeng said . Celebrity real estate developer Pan Shiyi, who has previously pushed for cities to publish more detailed air quality data and who is a delegate to Beijing's legislature, called for a 'Clean Air Act'. His online poll has received more than 29,000 votes, with 99 percent in favor. On Monday, Wang Anshun was elected Beijing's mayor after telling lawmakers the municipal government should make more efforts to fight air pollution, according to Xinhua. Last week, he announced plans to remove 180,000 older vehicles from the city's roads and promote government cars and heating systems that use clean energy. VIDEO: Beijing smog harming local children's breathing, say parents . VIDEO: Smog surrounds the streets and airport in Beijing .
Visibility was less than 100 metres in certain parts of eastern China .
Beijing officials ordered 103 heavy-polluting factories to suspend production .
Smog levels 20 times higher than World Health Organisation safety level .
By . Associated Press Reporter . PUBLISHED: . 16:31 EST, 30 January 2013 . | . UPDATED: . 02:31 EST, 31 January 2013 . Thick smog in China forced airlines to cancel flights, as factories in Beijing were temporarily shut down to ease the pollution. Street lamps and the outlines of buildings were barely visible in the Chinese capital, as pedestrians donned face masks to guard against the smog which has blighted parts of the country for a fortnight. The flight cancellations stranded passengers during the first week of the country's busiest period of travel, due to the Chinese New Year on February 10. Scroll down for video . Smog: The Central TV Tower in Beijing is barely visible after a fourth day of heavy smog . Safety measure: Officials in Beijing told 103 heavy polluting factories to cease operations in an attempt to reduce smog levels . More than 100 flights were canceled in the eastern city of Zhengzhou, 33 in Beijing, 20 in Qingdao and 13 in Jinan. The US Embassy reported an levels of PM2.5 - tiny matter that can penetrate deep into the lungs - was more than 20 times higher than World Health Organization safety levels over a 24-hour period. Liu Peng, an employee at a financial institution in Beijing, said he will keep his newborn baby indoors. He said: 'It's really bad for your health, obviously. I bike to work every day and always wear a mask. The pollution in recent years is probably due to the increase in private cars and government cars.' Visibility was less than 100 meters in some areas of eastern China, the official Xinhua News Agency reported. Every year, China's transport system bursts at the seams as tens of millions of people travel for the Lunar New Year holiday, in the world's largest seasonal migration of people. Invisible: Thick smog blankets buildings in Beijing last week, a city that has long had pollution problems . Reduction: Officials in Beijing government departments and state-owned enterprises to reduce their use of cars by a third . Ren Haiqiang, a bank worker said he had booked tickets to fly out of Beijing on Thursday to visit family in the coastal city of Dalian, but was now worried about flight cancellations. 'Traveling over the holiday is already a huge hassle, along with all the gift-giving and family visits. 'We thought flying would be the best way to avoid the crush, but if the weather continues like this we'll be in real trouble,' he said. Beijing's city government ordered 103 heavily polluting factories to suspend production and told government departments and state-owned enterprises to reduce their use of cars by a third, Xinhua said. The measures last until Thursday. Beijing's official readings marked the smog as at a 'severe' level and prompted the city government to advise residents to stay indoors. indoors: Women wearing masks doing their morning exercises in Beijing, China as people were warned to stay indoors as much as possible . Lasting: The government said that because there was no wind, the smog would not dissipate quickly . The government said that because there was no wind, the smog would not dissipate quickly. Patients seeking treatment for respiratory ailments rose by about 30 per cent over the past month at the Jiangong Hospital in downtown Beijing, Emergency Department chief Cui Qifeng said. 'People tend to catch colds or suffer from lung infections during the days with heavily polluted air,' he said. Air pollution has long been a problem in Beijing, with the city hitting its highest reading on January 12. Hospitalised: Patients seeking treatment for respiratory ailments rose by about 30 per cent over the past month at the Jiangong Hospital in downtown Beijing, Emergency Department chief Cui Qifeng said . Celebrity real estate developer Pan Shiyi, who has previously pushed for cities to publish more detailed air quality data and who is a delegate to Beijing's legislature, called for a 'Clean Air Act'. His online poll has received more than 29,000 votes, with 99 percent in favor. On Monday, Wang Anshun was elected Beijing's mayor after telling lawmakers the municipal government should make more efforts to fight air pollution, according to Xinhua. Last week, he announced plans to remove 180,000 older vehicles from the city's roads and promote government cars and heating systems that use clean energy. VIDEO: Beijing smog harming local children's breathing, say parents . VIDEO: Smog surrounds the streets and airport in Beijing .
20 times higher than World Health Organization government cars.' Visibility was less than 100 meters in some areas of eastern China, the ordered 103 heavily polluting factories to suspend production and told government