A spokesperson from the international airport in the Vietnamese capital, Hanoi, announced that all flights to and from the airport have been delayed or diverted to other cities on Friday due to heavy fog and worsening air pollution.
"Vietnam Airlines," an independent company monitoring air quality, reported that levels of hazardous fine particles known as PM2.5 in the air in Hanoi reached critically high levels, reaching 257 micrograms per cubic meter early on Friday.
The official at Noi Bai International Airport, who requested not to be named, stated, "All incoming flights have been diverted to other cities, including Hai Phong and Danang. No flights are currently allowed to depart."
Official media sources quoted airport authorities as stating that nearly 100 flights to and from the airport were affected.
The low-cost Vietnamese airline, "VietJet," reported that several of its flights scheduled to land in Hanoi were redirected to the city of Hai Phong.
An official told the Vietnamese newspaper "Tuoi Tre" that as of 8:00 AM (1:00 AM GMT), the airport had not received any incoming flights due to the dense fog in the area.
Between 3:00 AM and 8:00 AM, 12 domestic flights were redirected to Cat Bi Airport in Hai Phong and Da Nang International Airport. Another international flight failed to land at the airport.
In total, 55 flights at Noi Bai International Airport were affected by the fog.
The airport official referred to forecasts from the aviation meteorological center, indicating that regular flight operations are expected to resume by 10:00 AM local time.
To ensure safety, Vietnam Airlines postponed departure times for many flights to and from these airports by two to six hours, including eight flights from Ho Chi Minh City to Nha Trang, one to Thanh Hoa, and another to Thua Thien Hue.
Furthermore, nearly 30 domestic and international flights operated by Vietnam Airlines were delayed due to the domino effect.
Air pollution in Hanoi is consistently ranked among the highest rates in the world.
Last month, health authorities advised people to wear masks and reduce outdoor activities to mitigate the effects of pollution.