Heavy fog in northwest China\'s Xinjiang Uygur Autonomous Region forced an airport to close twice on Thursday, affecting 53 flights and leaving thousands of passengers stranded. Thick fog blanketed Diwopu International Airport in Urumqi, capital of Xinjiang, at around 0:30 a.m. forcing it to close, the airport\'s operating headquarters spokesman said. It reopened at around 9:20 a.m. as the fog began to fade. But the airport shut shortly after when fog returned at 10:40 a.m. Forty outbound flights were delayed. They were mainly going to cities like Beijing, Shanghai and Guangzhou, said the spokesman. He added that 13 flights bound for Urumqi from foreign countries and other parts of China were forced to land at other airports. Flights resumed at 2:50 p.m. when the fog dispersed, according to the spokesman.