Hong Kong: A march drawing tens of thousands of anti-government protesters in Hong Kong on New Year's Day spiralled out of control as police fired tear gas at crowds before halting the event.

Tens of thousands of people march through the streets of the Causeway Bay district of Hong Kong on January 1. Credit:Bloomberg

The violence broke out during the largely peaceful march as masses of citizens pressed authorities for further concessions in the Chinese-ruled city.

In the Wanchai bar district, some protesters had sprayed graffiti and smashed cash machines in an HSBC branch when riot police moved in, pepper-spraying crowds in a tense face-off. Tear gas was then fired into the crowds, affecting families and children.

The protesters, some with gas masks and clad in black, regrouped and formed their own lines as police blocked roads to prevent large crowds from completing the march as night fell.