Thousands march in Hong Kong to demand release of China's Ai Weiwei

Over one thousand protesters in Hong Kong took to the streets to demand the release of detained Chinese artist and human rights activist Ai Weiwei on Saturday, scuffling briefly with police.

The rally -- the largest in a string of protests across the city in recent weeks -- has underscored Hong Kong's growing role as a hotbed of support for Ai with local pro-democracy activists and artists ratcheting up pressure on Beijing over its heavy crackdown on dissidents, human rights lawyers and protesters challenging Communist Party controls and censorship.

Protesters held up banners with the words "Who's afraid of Weiwei" and banged on drums as they snaked their way through busy districts to the harbour-front Cultural Centre, where they sang, performed and chanted for Ai's release.

"It's had a lot of impact," said John Batten, a Hong Kong-based art critic and commentator who attended the rally.

"The message is purely about freedom of expression ... it's not just Ai Weiwei, there's a whole lot of
repression that's going on in China".

Organisers said 2000 people showed up, marshalled by a heavy police contingent through busy streets. While the event was largely peaceful, brief skirmishes with police broke out as tempers flared.

Graffiti images of Ai have also been appearing across the former British colony which reverted to Chinese rule in 1997, in subways, streets and prominent public spaces, spray-painted by an anonymous artist and sparking a police investigation.

Ai's detention in Beijing on April 3, after being prevented from boarding a flight to Hong Kong, has sparked criticism from Western governments, with US secretary of state Hillary Clinton saying she was "deeply concerned" about the clampdown.

Chinese authorities have been vague on Ai's charges, only saying he''s under investigation for "suspected economic crimes".