"Our intelligence has informed us that the Chinese government is moving troops to the Hong Kong border, and everyone should be calm and secure!" Trump tweeted after the landing in Pittsburgh for a production event.
Trump was criticized for saying very little about Hong Kong's protests and instead focusing more on his hopes for a trade deal with Beijing.
Tuesday's demonstrations became violent after protesters closed the airport and crashed riot police, raising fears that Beijing could move closer to considering violence.
China regularly maintains a troop presence near the Hong Kong border. Trump's tweet on military movements probably referred to the current US assessment that, according to several officials, China has stationed some mobile forces along the border in locations where they could possibly be stationed.
Several officials noted that the presence of troops has been widely observed and publicly reported in recent days.
Tuesday was the second day that protesters gathered at the Hong Kong airport made flight cancellations. The protests, however, have a much longer history: protests began in earnest in June to oppose a bill that would allow Hong Kong to deliver individuals to mainland China.
Amnesty International said this week that the Hong Kong police had violated human rights by cracking down on gas, rubber bullets and peppercorns in protest against the demonstrators.
Chinese officials have accused the US and other foreign governments of standing behind the protests for democracy. The US has denied any role and Trump also seemed to reject the proposal on Tuesday when he tweeted that "many blame me and the US for the problems in Hong Kong ̵
"Hope nobody is killed"
Shortly after describing the riots in Hong Kong as a "tough situation", he told reporters he hopes the situation will improve. for everyone, including China.
When chaos broke out on television by demonstrators and riot police at Hong Kong International Airport, Trump told reporters in New Jersey that he wished the situation "works for freedom." "I hope nobody gets hurt and I hope no one is killed. "
A senior government official said," The United States continues to monitor the situation in Hong Kong, and we urge all sides to remain calm and secure. and peacefully. "
" As the President said, "They are looking for democracy and I think most people want democracy." Freedom of expression and association are core values that we share with the people of Hong Kong, and these freedoms should be protected, "the official added.
"The United States rejects the idea that we support or encourage the demonstrations "The officer said and repeated Trump's earlier tweet."
Another senior government official told CNN Tuesday "The US believes that China's military intervention in the protests is likely due to Beijing's authorities Lost control.
The official said, loss of control could be defined as a disruption of business in Hong Kong.
In the US, surveys conducted after the violent repression of Tiananmen Square protests in 1989 showed that public support for China had dramatically declined. Under Chinese law, there were no interventions by the Chinese military in Hong Kong under 30 years of age good idea, said the official.
When China intervenes militarily, Congress explodes and there are negative consequences, the official added.
However, several US officials told CNN that the troop movement near the Hong Kong border is a tactic they were expecting from Chinese President Xi Jinping, who laid the groundwork for action.
Xi is also preparing for this opportunity by addressing his message with news of unrest and violence to the Chinese public, so that the step for the mainland audience is not a shock when Beijing intervenes.
Pushing A report on support for the US and other states for the demonstrators could also allow Xi to justify intervention against the Chinese people.
For the moment, however, it seems that Xi is still weighing the potential costs and benefits of an intervention. US officials told CNN they were waiting to see if he would take the next step and instruct the Chinese military to stop the protests from reacting.
Several US officials have told CNN that there is hope that China will not ultimately intervene and that the potential economic impact, along with obvious safety implications, is a major problem.
He believes it is under some US Civil servants still have a window for China to avoid intervention, but that would require the Hong Kong authorities to act, or that non-protesting locals begin to exert social pressure on protesters to ease tensions.
In the meantime, US and Chinese officials appear to be engaged in open dialogue.
Secretary of State Mike Pompeo met with a top Chinese diplomat in New York on Tuesday, and the two had an "expanded exchange of views on US-China relations," according to Foreign Ministry spokesman Morgan Ortagus.