A six-hour thunderstorm in Chengdu, Sichuan province, on Thursday delayed 704 scheduled flights and stranded 14,000 passengers.

"The first flight was scheduled to leave for Lhasa from the Shuangliu International Airport in Chengdu before 6:10 am. But due to excessive rainfall, the airport was closed till 8:30 am when a plane left for Lanzhou, Gansu province," said Lu Junming, an airport information officer.

As of press time on Thursday, nearly 5,000 passengers were still stranded at the airport.

"The thunderstorms are not expected to last long. So it will not have a major adverse impact on flights on Friday," Lu said.