The family of the 70-year-old man who died after he was hit in the head by a brick during a recent violent protest in Hong Kong hope the police can arrest the murderer as soon as possible.

"All of this happened suddenly, which is difficult for us to accept," the man's son said at a press briefing held by the Hong Kong Federation of Trade Unions on Friday, adding that his father just did what Hong Kong residents should do.

According to reports, the man who worked as a sanitation worker, sustained critical head injuries while clearing the barricades outside a metro station in Hong Kong's New Territories.

A spokesperson from the federation has pledged the organization's help to safeguard all the relevant rights and interests of the deceased.

The man was the first innocent civilian to die since the now-withdrawn ordinance amendments concerning fugitive transfers sparked unrest in the city.

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