More than 3,600 people were stranded at an airport in northwest China's Xinjiang Uygur Autonomous Region Tuesday after thick fog affected 76 domestic flights, Xinhua reported. Visibility in the Diwobao International Airport in Urumqi, the regional capital, dropped to 200 meters after 11 a.m. and then remained at about 300 m, far less than the required level for take-offs. Six flights were canceled, 11 were diverted to other cities and59 were delayed, according to the airport administration. Airport staff began to arrange flights in the evening to move the stranded passengers. The heavy fog also caused a road pile-up in the morning, killing three people and injuring two others in Fukang City after a truck-car collision that triggered a number of other crashes. Traffic police were investigating the fatal accident.