President Trump tweeted Tuesday afternoon that he had been informed by U.S. intelligence that "the Chinese Government is moving troops to the Border with Hong Kong," adding, "Everyone should be calm and safe!"

Why it matters: There are fears of a crackdown from Beijing on the protestors, who clashed Tuesday with police while occupying Hong Kong's international airport. It had been publicly reported that Chinese armed police had massed in Shenzhen, a city near Hong Kong on the Chinese mainland. Trump has until now taken a hands-off approach to the escalating situation in Hong Kong, suggesting that President Xi Jinping should handle the "riots" as he sees fit.

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