* Hong Kong airport reopens after violent protests
* Airport obtains injunction to block protesters
* Protesters angry over perceived erosion of freedoms in Hong Kong
* Hundreds of weary travellers queue for rescheduled flights
* Trump says China moving troops close to border, urges calm (Adds details on protesters, U.S. Navy ships, property developer adverts)
By Felix Tam and Marius Zaharia
HONG KONG, Aug 14 (Reuters) - Hong Kong's airport resumed operations on Wednesday, rescheduling hundreds of flights that had been disrupted over the past two days as protesters clashed with riot police in a deepening crisis in the Chinese-controlled city.
Ten weeks of increasingly violent clashes between police and pro-democracy protesters, angered by a perceived erosion of freedoms, have plunged the Asian financial hub into its worst crisis since it reverted from British to Chinese rule in 1997.
A few dozen protesters remained at the airport on Wednesday while workers scrubbed it clean of blood and debris from overnight. Check-in counters reopened to queues of hundreds of weary travellers who had waited overnight for their flights.
Police condemned violent acts by protesters overnight and said on Wednesday a large group had "harassed and assaulted a visitor and a journalist". Some protesters said they believed one of those men was an undercover Chinese agent, while another was confirmed as a reporter from China's Global Times newspaper.
Five people were detained in the latest disturbances, police said, bringing the number of those arrested since the protests began in June to more than 600.
Operations at the airport were seriously disrupted as riot police used pepper spray to disperse thousands of black-clad protesters.
Hong Kong's Airport Authority said on Wednesday it had obtained an interim court injunction to stop people from obstructing airport operations. It said protesters could only demonstrate in designated areas.
Dicky, a 35-year-old protester at the airport for more than two days, said protesters would obey the injunction if it meant they had to leave, despite anger felt towards the government and the police, plus triad gangs who have been blamed for attacking some protesters.
"We saw the government arrested many people, many are injured, some committed suicide. We will continue to fight for what we deserve otherwise all of that would have been in vain," he said, declining to give his full name.
In Washington, U.S. President Donald Trump said the Chinese government was moving troops to the border with Hong Kong and urged calm.
He described events in Hong Kong as tricky but said he hoped it would work out for everybody, including China, and "for liberty" without anyone getting hurt or killed.
Hong Kong leader Carrie Lam said on Tuesday the city had been pushed into a state of "panic and chaos".
China condemned some protesters for using dangerous tools to attack police, saying the clashes showed "sprouts of terrorism". The protests represent one of the biggest challenges for Chinese President Xi Jinping since he came to power in 2012.
In a potentially ominous sign, a front-page commentary in the overseas edition of the Communist Party's official People's Daily newspaper said on Wednesday that using the "sword of the law to stop violence and restore order is overwhelmingly the most important and urgent task for Hong Kong".
Demonstrators say they are fighting the erosion of the "one country, two systems" arrangement that enshrined some autonomy for Hong Kong when it returned to China in 1997.
The protests began in opposition to a now-suspended bill that would have allowed the extradition of suspects for trial in mainland China but have swelled into wider calls for democracy.
Flag carrier Cathay Pacific Airways published a half-page advertisement in the Hong Kong Economic Journal on Wednesday pledging its support for the government and calling for the resumption of the rule of law and social order.
"Rule of law is the cornerstone of prosperity and for people to live and work in peace. We have to act now to oppose violence, to resume the peace, and to maintain the prosperity and stability of Hong Kong," it said.
Cathay's largest shareholder, Swire Pacific, said in an advertisement in the same paper that it supported the carrier's "zero tolerance on illegal activity".
China's aviation regulator demanded last week that Cathay suspend personnel who engaged in or supported protests in Hong Kong from staffing flights into its airspace. The carrier later suspended two pilots.
Property developers Henderson Land Development, Cheung Kong Holdings and Sun Hung Kai Holdings also took out newspaper advertisement in support of the government on Wednesday.
ISSUES AT STAKE
Some tourists stopped to look at posters put up by protesters in the airport's arrival hall.
"To do a protest you have to get people's attention. Protests at the airport can let the whole world know what is happening in Hong Kong," said Canadian tourist Jason Grafstrom.
Check-in operations at the airport were suspended late on Tuesday afternoon, a day after an unprecedented shutdown. Thousands of peaceful protesters had swarmed the arrivals and departures halls earlier on Tuesday, chanting, singing and waving banners.
Some protesters used luggage trolleys to blockade the doors to customs checkpoints. Protesters scuffled with police and several police vehicles were blocked amid heated scenes later on Tuesday night, according to Reuters witnesses.
A policeman was seen drawing his gun at one point.
The United Nations human rights commissioner, Michele Bachelet, urged Hong Kong authorities to exercise restraint and investigate evidence that tear gas was fired at protesters in ways banned under international law.
China responded by saying her comments sent the wrong signal to what it described as violent criminal offenders.
As Hong Kong's political crisis deepens, China denied a request for two U.S. Navy warships to visit Hong Kong in the coming weeks, U.S. officials said on Tuesday. One official said no specific reason was given.
Forward Keys, a flight data company, said the crisis had deterred people from making travel plans to the city, citing a 4.7 percent fall in long-haul bookings to Hong Kong between June 16 and Aug. 9 compared with the same period last year.
Statements of apology from protesters were displayed in the airport on Wednesday, promising to allow passengers to depart, to assist medical staff to carry out their duties and not to hinder the work of the press.
"We are not afraid of facing the issues directly...only afraid of losing your support to the whole movement due to our mistake, and that you give up on fighting." (Reporting by Tom Westbrook, Donny Kwok, Clare Jim and Twinnie Siu in HONG KONG and Andrew Galbraith in SHANGHAI; Writing by Farah Master Editing by Paul Tait)
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