CHENGDU -- About 15,000 passengers have been stranded at an airport in Chengdu, capital of Sichuan province, as a heavy fog shrouded the southwestern city on Monday.

The fog started around 1:00 am, reducing visibility to 50 meters on the runways and landing fields at Chengdu Shuangliu International Airport.

The airport issued an alert for flight delays at 6:45 am. Only 13 flights took off from 6:00 a.m. to 9:00 a.m., less than 10 percent of the ordinary number. Flights started to fully resume at 11:22 am.

As of noon, a total of 44 flights had been canceled and 185 outbound flights delayed. All incoming and outbound flights will be delayed for over five hours.

The airport expects that the first group of stranded passengers will be able leave around 4:00 pm and it will finish transporting all stranded passengers after midnight.