Hong Kong (Reuters) - China said on Sunday it opposes all kinds of illegal behavior in Hong Kong that undermines social stability as pro-democracy supporters geared up for a showdown with police as they push demands for greater political freedoms in the former British colony.

A spokesperson for China's Hong Kong and Macau Affairs Office added that the central government fully supports the Hong Kong government's handling of the matter in accordance with the law.

Violent clashes between Hong Kong riot police and students galvanized tens of thousands of supporters of the city's pro-democracy movement and kick-started a plan to lock down the heart of the Asian financial center early on Sunday.

(Reporting By Anne Marie Roantree; Editing by Nick Macfie)

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