HONG KONG — Antigovernment protesters are expected to kick off a three-day demonstration on Friday at Hong Kong’s international airport, a symbolic attack on both a global transit hub and the city’s closely guarded reputation for order and efficiency.

The protest, which is scheduled to begin early Friday afternoon in the airport’s arrival hall, comes as Hong Kong reels from its worst political crisis since Britain handed the former colony back to China in 1997, and less than a week after protests and a general strike caused chaos in the city and led to 148 arrests.

In recent days, mainland Chinese officials have issued stern warnings to protesters about the risks of continuing their broad campaign for political reforms. The movement began in opposition to a bill that would have allowed extraditions to the mainland — where the courts are controlled by the ruling Communist Party — but has since expanded to include a range of other demands for greater democracy.

The protests this summer began two months ago with a mostly peaceful march that drew hundreds of thousands of people in a city of about seven million. Demonstrations have since continued on a smaller scale, though on Monday they reached a new pitch, as protesters followed their call for a general strike by disrupting flights and snarling commutes.