The worldwide airport, one of the world's busiest, said in a statement on Monday that the demonstration has "seriously disrupted" airport operations.
The company is caught in crosswinds between Beijing and pro-democracy groups in Hong Kong after the Chinese civil aviation regulator demanded it suspend personnel who engaged in or supported the protests from staffing flights into its airspace.
Lam said last month that the bill has failed but has refused to withdraw it completely, leading to accusations that she's simply stalling for another chance to ram it through.
Violent protests are driving Hong Kong down a "path of no return", the city's leader warned Tuesday as its airport struggled to recover from an unprecedented shutdown triggered by a rally and authorities in Beijing sent more ominous signals that the unrest must end.
On Monday, the Canadian prime minister, Justin Trudeau, said he was very anxious about events in Hong Kong, which has a large Canadian population, and urged Chinese authorities to handle the protests there with tact.
But if you check out the websites of major airlines, many flights still remain "cancelled".
Hong Kong leader Carrie Lam warned Tuesday of the risky consequences facing the city, one of Asia's most important financial hubs, if escalating violence at the rallies was not curbed.
Hong Kong Chief Executive Carrie Lam speaks during a news conference on August 5 about protests against her extradition bill, for which she has apologized but not completely withdrawn.
CRITICAL JUNCTURE China said on Monday protests in the Asian financial hub had reached a critical juncture.
A train station in Kwai Fong filled with smoke after about a dozen police officers fired tear gas inside. So, what exactly is happening in Hong Kong now and why are people protesting?
China's military - the People's Liberation Army - has a garrison of 6,000 soldiers in Hong Kong.
Passengers with luggage were being checked in for flights, and only a handful of the thousands of protesters who flooded into the airport a day earlier remained in the building.
Ms Lam added that her role was to "ensure that Hong Kong remains a safe and orderly" city.
Many protesters are fleeing in advance of an expected police clearance operation, which some fear could turn violent.
The airport was operating normally as of now, staff at the airport's customer service hotline said by phone.
In a statement, the airport said operations had been "seriously disrupted" by the public assembly. Hong Kong's airport is the eighth busiest by passenger traffic, handling 73 million passengers a year.
But he said he sympathised with the protesters despite the disruption.
The airport was the latest focus of protests that began two months ago.
Another protester, who identified herself only as Bea, said she took the day off from work to express her outrage because "I feel that I have to do something".
The controversial extradition bill was proposed on April 3 as a response to the Hong Kong government's inability to extradite a Hong Kong man to Taiwan after he allegedly killed his girlfriend on a trip there. "I hope the government will hear us".