However, others - including a fashion designer and human rights activist - blamed the chain store for testing the limits of the law.

Acting Superintendent Paul Cheng Fuk-chuen of the Organised Crime and Triad Bureau warned those who had bought the T-shirts not to wear them because by doing so they would break the law and could face penalties of up to seven years' jail and a HK$250,000 fine.

'Anyone who is found in possession or control of any symbol relating to any triad society is breaking the law,' he said. 'I think the [design] industry has the responsibility to check [the law]. If necessary, they should seek legal advice.'

Mr Cheng also warned the media not to publish the full name of the society, and to blur the characters on the T-shirt in photos.

But the name of 14K, and other triad societies, can be found with detailed descriptions on police and other government websites - and in the press release giving details of yesterday's arrests.

Hong Kong Journalists Association chairwoman Fan Ho-tsai said the practice of not using a triad society's full name in news reports had long been abandoned. But she believed the gangs should not be publicised unless absolutely necessary.

Nine men and nine women, including shopowner Douglas Young, a designer, salespeople and other G.O.D. staff members were arrested on suspicion of violating the Societies Ordinance. They were all released on bail last night. No one has been charged.

A total of 88 T-shirts and more than 500 postcards were seized during lunchtime raids on the chain's shops in Causeway Bay, Central and Tsim Sha Tsui, as well as its offices and warehouse in Yuen Long. The T-shirts sold for HK$280 and the postcards HK$5 each.

G.O.D. marketing manager Cherry Ma Kit-ling said the design was not meant to draw any connection to the triad society and the company found such accusations frustrating.

'The sales of the T-shirt are not even good,' she said. Less than one-fifth of the 100 T-shirts produced had been sold since mid-September. Buyers of the T-shirts can get a refund or call the police on 2527 7887.

Former film producer and scriptwriter Jimmy Pang Chi-ming said the arrests amounted to white terror.

'Something we have never taken seriously could in fact land us in jail.'

Cultural commentator Leung Man-to said police were overreacting and it would not lead to self-censorship among the creative media.

But fashion designer William Tang said there was a difference between artworks with triad elements and those that sold them as a brand.

'A lot of movies and dramas centre on the rituals and life of triad members. But it is a different matter to display a triad name as a brand.'

Human rights activist Law Yuk-kai said G.O.D. might have gone too far with its T-shirt. 'The postcard is all right though, it reads 14K Gold, not just 14K.'