By Brenda Goh and Tom Westbrook

HONG KONG - Flight check-in services have been suspended at Hong Kong's international airport, the airport authority said on Tuesday, citing disruptions caused by anti-government protests.

A state of “panic and chaos” exists in Hong Kong, the city’s embattled leader said on Tuesday, defying calls to quit as the stock market tumbled, airlines flagged further flight disruptions and anti-government protesters filled the airport.

Unrest has roiled the former British colony for 10 weeks this summer, as thousands of residents chafe at a perceived erosion of freedoms and autonomy under Chinese rule.

The increasingly violent demonstrations have plunged the Asian financial hub into its most serious crisis in decades, presenting Chinese leader Xi Jinping with one of his biggest challenges since he came to power in 2012.