Pro-democracy protesters have clashed with riot police outside the headquarters of Hong Kong's government.
Government offices and shops were forced to temporarily close while the stand-off continued.
The head of a parliamentary committee banned from entering Hong Kong has told ITV News the actions of the Chinese government are "a very worrying development".
MPs are pressing for an emergency Commons debate after China said it would not let the Foreign Affairs Committee enter the former British colony.
The committee had been planning the visit as part of an inquiry into relations with the UK 30 years after the joint declaration which led to the handover of Hong Kong to China in 1997.
The Chinese government has claimed the trip would be a "highly inappropriate act which constitutes interference in China's internal affairs".
Committee chair Sir Richard Ottaway said: "For them to be banning a parliamentary committee from one of their G20 partners from visiting Hong Kong I think is a very worrying development about the direction of travel of China."
The Democratic presidential candidate may also have shown his cards on his choice of running mate.
The US president also shared a post on Twitter accusing Dr Anthony Fauci of misleading the public over hydroxychloroquine.
Fears over an impending second wave of coronavirus dominates Wednesday’s front pages.