Andrew Wang left home at six in the morning on Friday. He drove as fast as he could to reach Beijing Capital International Airport just 2 minutes before the check-in counter was supposed to close.

The west section of the Chang'an Avenue in Beijing on Friday, October 26, 2007. Thick fog blanketed Beijing's main airport on Friday, leaving thousands of air passengers stranded. [ Xinhua Photo]

He heaved a sigh of relief when the staff at the counter told him: "Don't worry." But his relief was short-lived, for he soon found out he had a world to worry about. His flight had been delayed.

He took the break to have breakfast. After some hours, it was time for lunch. He had his cup of evening coffee too at the airport. It was 6 pm and the plane he was supposed to take was still grounded in Qiqihar, a city in Northeast China's Heilongjiang Province.

Wang was among thousands of passengers who were stranded at Beijing airport because of the heavy fog shrouding the city. Almost all the flights were delayed or cancelled, an airport spokesman surnamed Jin said.

About 1,300 flights can take off or land in Beijing in a day. But till 6 pm on Friday, passengers had boarded only five flights and no information was available on when they would take off.

Thousands of passengers were left stranded and a demonstration flight of the new Airbus A380 superjumbo was among dozens of flights delayed or cancelled.

Almost every airline counter was overcrowded, with passengers seeking the latest information on flights. But most of them maintained their calm because they realized the bad weather was to blame for the delay.

Though foreign passengers also knew the cause of the delay, they were frustrated at the lack of information. Some wondered whether their flight had been canceled or just delayed.

A man waiting at a China Eastern Airlines counter said passengers had to wait for 5 hours before their flight time was announced.

"I didn't want to lose my place in the queue so I stood near the counter for 5 hours without even going to the bathroom or to have a cup of coffee," said an American passenger, who preferred to be called by his Chinese name Wei Sizhong.

But he had to return to his Beijing home after 6 hours because his flight had been canceled. He is trying to book a seat on another flight to Shanghai, he said.

Swedish national Lehman said: "The airport authorities should at least tell us what is happening."

Many flights had been canceled on Friday evening, spokesman Jin said. Whether the passengers can fly to their destinations on Saturday depends on the weather condition.

The municipal observatory increased the fog warning level from yellow to orange at 5:20 am on Friday as the fog grew thicker. The highest fog warning level is red.

The fog is expected to linger overnight, but it may clear on Saturday morning with the help of rainfall, the Beijing Meteorological Observatory said.

"The fog will linger until tomorrow morning, as the humidity remains high and the wind is not strong enough to disperse the fog during the night," said Guo Jinlan, chief weatherman with the municipal observatory.

"There will be rainfall early on Saturday morning, which will help to clear the fog tomorrow morning," Guo said.

Dense fog was also reported in the city's neighboring Hebei Province and Tianjin Municipality and the bureau closed major highways linking them to Beijing and the capital's eastern sixth ring road for safety reasons, according to the office. They will remain closed until the fog clears.

The thick haze exacerbated the city's pollution as the municipal observatory predicted that the air pollution index from 20:00 pm Friday to 20:00 pm Saturday would stand between 120 to 150, meaning the air is slightly polluted.

Experts warned the elderly and children to stay indoors to avoid contracting respiratory diseases.

3500 people affected in Guangzhou

In Guangzhou's Baiyun Airport, 17 flights were delayed or cancelled yesterday. Over 3500 people have been affected by the flights, reports Life of Guangzhou.

Flights to Yiwu, Shanghai and Dalian cities have been delayed for 4 hours and 600 people were maintained in the airport.