A top Chinese military commander has declared it would take the army 10 minutes to reach Hong Kong, as the financial hub braces for more demonstrations over the coming weekend.
The chilling message was sent by the Eastern Theatre Command of China's People's Liberation Army.
Today, thousands of Chinese troop personnel waving red flags paraded at a sports stadium in a city across the border from Hong Kong a day after the warning was issued.
Members of China's paramilitary People's Armed Police were seen marching and practising crowd-control tactics the complex, in what some have interpreted as a threat against pro-democracy protesters.
Hong Kong's government has refused to talk with demonstrators who have protested since early June to demand expanded political rights and the scrapping of legislation that could have seen criminal suspects sent to China.
Vehicles belonging to the paramilitary People's Armed Police were arrayed Friday in Shenzhen, a city just across from Hong Kong.
Parking spaces at the stadium were filled with more than 100 dark-painted paramilitary vehicles, including troop trucks, armoured personnel carriers, buses and jeeps.
At least three were armoured wheel-loaders, and two vehicles carried water cannons.
Satellite images taken on Tuesday showed Beijing had apparently assembled some 500 armoured vehicles to a sports centre in Shenzhen across the harbour from Hong Kong.
Hong Kong police officers said they weren't aware of plans for Chinese forces to join efforts to quell the demonstrations.
The protests have been marked by increasing violence and shut down the Hong Kong airport earlier this week.
The United States said yesterday that it was concerned about movements of Chinese forces on the border with Hong Kong and urged Beijing to honor the territory's autonomy.
But US President Trump praised Chinese President Xi Jinping, calling him a "great leader" and saying he could quickly resolve the unrest in Hong Kong if he wanted to.
He also suggested trade talks with China could wait until tensions in Hong Kong eased. He tweeted: "Of course China wants to make a deal. Let them work humanely with Hong Kong first!"
Meanwhile, protesters announced plans to withdraw as much money as possible from banks or change their currency into US dollars to disrupt the banking system.