The man was not a participant in the anti-government protests that have taken over the city this summer and often ended in violent clashes with the police.

But it underscored one of the movement’s central grievances over police brutality and bolstered demands for an independent investigation into their use of force.

Related: Beijing’s attempt to manipulate the narrative about the protesters in Hong Kong as violent, foreign-backed ruffians is a failure of Chinese “soft power,” writes our New New World columnist, Li Yuan.

Another angle: An employee of the British Consulate in Hong Kong vanished after crossing into mainland China this month, raising fears that the authorities might be targeting travelers they suspect of supporting the protesters.