People pass a suitcase as they line up to enter a railway station in Beijing, February 15, 2015. Chinese Ministry of Transport said a total of 2.807 billion trips are expected to be made during the 40-day Spring Festival travel rush, which started on February 4 and will last until March 16, Xinhua News Agency reported. (Photo by Reuters/Stringer)

A migrant carries his belongings as he arrives at the Beijing railway station to catch a train in Beijing, Friday, February 13, 2015. (Photo by Andy Wong/AP Photo)

A dead sperm whale is seen on the beach on March 18, 2012 in Yancheng, Jiangsu Province of China. Four giant sperm whales, which were found beached on the beach of Xintan Salt Field on Friday, died on Saturday despite rescue efforts. (Photo by ChinaFotoPress)

A street cleaner demonstrates his martial arts skills in front of a closed shop near Beijing's Tiananmen Square September 2, 2015 as the capital prepares for tomorrow's parade. (Photo by Damir Sagolj/Reuters)

A citizen rides in smog on December 20, 2016 in Jinan, Shandong Province of China. Air quality index (AQI) readings exceeded 400 and some schools have suspended classes in Jinan. (Photo by VCG/VCG via Getty Images)

A woman walks up the steps decorated ahead of the Chinese New Year festival in Beijing, China, Thursday, January 12, 2017. The Chinese Lunar New Year is the most important holiday for Chinese and hundreds of millions are expected to return to their hometown to spend the new year with their family and relatives. (Photo by Ng Han Guan/AP Photo)

Participants pose as they take part in a bodybuilding and fitness event named “China Fit”, in Beijing, China, June 15, 2016. (Photo by Reuters/Stringer)

Taiwanese and Chinese nationals suspected of telecom fraud are surrounded by China police SWAT team and Cambodia police as they were deported to China at the International Airport of Phnom Penh, June 24, 2016. Scores of Chinese police officers swarmed the tarmac at Phnom Penh International Airport on Friday as 39 suspects arrested for their involvement in an alleged telecom scam were herded onto a chartered plane bound for China – including 25 Taiwanese nationals, whose government unsuccessfully attempted to have them repatriated. (Photo by Samrang Pring/Reuters)