Hong Kong - A 40-year-old former Calyon Bank warrants trader was Friday named as the key suspect in a multi-million US dollar stocks scam in Hong Kong.

Raymond Ng is alleged to be the mastermind behind the scam which netted around 13 million US dollars over two years and led to the arrest of 29 people, according to the Hong Kong Standard.

Traders at Standard Securities Asia, Citigroup Global and Dresdner Kleinwort Securities were also among those arrested in the investigation, according to the newspaper.

Ng, also known as Sai Ray or Ray Junior in the warrant market, allegedly set himself up as director of an investment company and handed out bribes to manipulate the market, according to the Standard.

He gave hundreds of thousands of US dollars in bribes to four traders in warrant issuing firms to quote him favourable bids and ask prices, the newspaper quoted investigators saying.

Anti-corruption investigators swooped on offices across Hong Kong earlier this week to arrest 29 people in the ongoing investigation into the alleged scam.

Six stockbrokers and four traders were among those arrested although by Friday none had yet been charged by Hong Kong's Independent Commission Against Corruption.

Warrant trading has become increasingly popular among Hong Kong's stock market players in recent years and constitutes one-fifth to one-third of daily trading volumes on the Hang Seng Index.

The recent economic slowdown has seen stock prices in Hong Kong fall from a peak of nearly 33,000 points last October to a current level of just above 24,000 points. (dpa)