(Bloomberg) — Hong Kong’s airport resumed normal operations after a chaotic night of protest in which demonstrators beat and detained two suspected infiltrators and President Donald Trump warned of Chinese troops massing on the border.Only a few dozen protesters remained at Hong Kong International Airport as of 8:30 a.m. Wednesday, most having caught the last trains away from the airport rather than face dispersal by authorities. Flights appeared to be largely running as scheduled. The Airport Authority said it had obtained a court order to bar people from “unlawfully and willfully” obstructing airport operations.Earlier Tuesday, hundreds of people staged a sit-in at the departure gates, disrupting flights at one of Asia’s busiest airports for the second straight day. In an early-morning statement, Hong Kong’s government condemned the violence at the airport and said it would punish those responsible.The images of riot police clashing with protesters at the airport further dented Hong Kong’s reputation as a stable place to do business during the 11th week of protests against a bill allowing extraditions to China. The escalating stakes have raised fears that China would mobilize forces to restore order, a move that could scare away foreign companies and further erode the financial hub’s autonomy.Trump stoked fears of a Chinese intervention, saying in a tweet that reports from U.S. intelligence agencies show mainland troops massing at the border with Hong Kong. He later told reporters that China is facing a “tough situation” in the city: “I hope nobody gets hurt. I hope nobody gets killed.”A U.S. State Department official urged China to respect the agreements it made when taking control of Hong Kong from the U.K. and allow the city to “exercise a high degree of autonomy.” The statement — from an official who asked not to be identified — was the most forceful to date from the U.S.At the airport, chaotic scenes emerged when protesters beat a man they accused of being a mainland police officer and then declined to let paramedics evacuate him from the scene. They eventually relented after police urged them to let the man go.Afterwards, riot police briefly entered the airport after clashing with protesters who blocked roads to prevent officers from leaving the scene. Demonstrators then detained a second mainland Chinese man who turned out to be a reporter for the Global Times newspaper, which is published by the Communist Party. They tied him to a luggage trolley before allowing paramedics to evacuate him.–With assistance from Annabelle Droulers, Yvonne Man and Karen Leigh.To contact the reporters on this story: Fion Li in Hong Kong at firstname.lastname@example.org;Stephen Engle in Beijing at email@example.comTo contact the editors responsible for this story: Brendan Scott at firstname.lastname@example.org, Daniel Ten KateFor more articles like this, please visit us at bloomberg.com©2019 Bloomberg L.P.