Dozens of riot police and pro-democracy protesters clashed at Hong Kong International Airport on Tuesday night, after flights were disrupted for a second day in a row.

Evening scuffles broke out between demonstrators and police outside the airport after some protesters blocked several police vehicles. Officers with shields pushed back protesters near one of the airport entrances and used pepper spray to break up the crowd.

Police said they were trying to get in to the airport to escort an injured man to an ambulance who protesters detained on suspicion of being an undercover agent.

Hong Kong's Airport Authority said operations at the airport, which is one of the busiest in the world, had been "seriously disrupted" by the demonstrations. The authority said protesters blocked passageways to the airport's restricted area, blocking passengers from continuing to immigration.

Hundreds of flights were canceled or suspended at the airport on Monday and Tuesday after protesters  staged a multi-day sit-in in the main hall of the airport, using luggage trolleys to stop passengers from passing through security gates.

Read more:  Hong Kong pro-democracy movement: A timeline

Trump says Chinese troops moving towards border

US President Donald Trump wrote on Twitter that China's government was moving troops to the border with Hong Kong, citing US intelligence.

"Everyone should be calm and safe!" he added. It was unclear whether Trump was referring to fresh developments or movements near the border that had already been reported.

Paramilitary police are assembling in Shenzhen for exercises that some view as a message from Beijing to protesters. Chinese state media earlier aired video showing troop carriers and personnel carriers that were heading to the city of Shenzhen, near the border with Hong Kong.

China has not yet threatened to use its army, although legal experts say that Beijing might use anti-terror laws in order to quell the demonstrations.

China's mission to the United Nations also issued a statement on Tuesday accusing the Hong Kong protesters of smashing public facilities, blocking public transportation and using lethal weapons, saying that the movement is "showing a tendency of resorting to terrorism."

Protests began 10 weeks ago in opposition to a bill that would allow the territory to extradite people facing criminal charges to mainland China, but the movement has expanded to include wider calls for democracy.

EU urges restraint on all sides

The European Union on Tuesday called on all parties involved to quickly de-escalate the situation and establish talks to defuse tensions.

"In light of the continuing unrest and the increase in violent incidents in Hong Kong, it is crucial that all sides exercise restraint, reject all kinds of violence and take urgent steps to de-escalate the situation," an EU spokesperson said in a statement.

Speaking at a press conference earlier Tuesday, the semiautonomous territory's leader, Carrie Lam, said demonstrations could push Hong Kong "down a path of no return" and claimed that protesters had created "a state of panic and chaos."

Clashes between police and protesters in Hong Kong have grown increasingly violent, with authorities repeatedly using tear gas and bean bag pellets fired at close range to disperse the demonstrations.

rs/   (AP, AFP, dpa, Reuters)

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