Bangladesh, Nov. 15 -- year-old man has died in Hong Kong after being struck on the head during clashes between government supporters and protesters.

Officials said the man was on a lunch break from his job as a cleaner when he was hit in the head by "hard objects hurled by masked rioters".

It comes as China's president Xi Jinping said the "one country, two systems" system was being "challenged".

Hong Kong has been dogged by more than five months of political unrest.

Less than a week ago, Alex Chow, a 22-year-old student, died after falling from a building during a police operation.

What happened to the man?

The 70-year-old cleaner was hit in the head during a protest on Wednesday in the Hong Kong border town of Sheung Shui.

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