Tear gas as thousands defy police in latest Hong Kong march

Hong Kong police fired tear gas and water cannon Saturday as thousands of democracy protesters defied authorities in another unsanctioned march after Beijing vowed to tighten control over the unrest-plagued city.

Commercial districts on the main island became a battleground as crowds of black-clad protesters, many wearing face masks despite a recent ban, clashed with riot police for hours.

Hardcore protesters hurled bricks and petrol bombs and vandalised multiple subway stations and businesses perceived to be pro-China - including the office of China's state-run Xinhua news agency, which had its windows smashed.

Police responded with sustained volleys of tear gas, scattering protesters with water cannon trucks and making dozens of arrests.

After one clash an AFP reporter saw around 100 people being taken away in three coaches.

Among those caught up in the tear-gas clouds were rugby fans who had gathered in bars in Wanchai district to watch the World Cup final.

Hours later revellers in a nightclub district had a similar experience as party-goers scrambled for cover and bars shut their windows.

A medical volunteer also sustained burns to his back after he was struck by a tear-gas canister, footage showed.

By evening, the clashes had moved across the harbour to Mongkok and Tsim Sha Tsui, two areas that have seen regular skirmishes in recent months.

In a statement Xinhua condemned the "barbaric acts" of the protesters who targeted their office.

The latest unrest came after China warned on Friday that it would not tolerate any challenge to Hong Kong's governing system and planned to boost patriotic education in the city, which has seen 22 consecutive weekends of youth-led protests.