Investigators of events behind Griffin's bankruptcy are believed to have uncovered unauthorized trading by Scott Szach, its chief finanical officer, which is estimated to have cost the firm between $1.5 million and $2 million.

It is not clear whether Szach's alleged dealings are connected with John Park, the Korean-born trader, whose losses of almost $10 million on German government bonds forced Griffin and GLH (Derivatives), a trading firm of which he was a member, into insolvency just before Christmas.

Griffin's collapse has caused consternation on the London International Financial Futures and Options Exchange (Liffe). About 100 traders who used the company have been temporarily forced out of business after a big chunk of their clients' money was taken by Mees Pierson, the Dutch bank which cleared deals on behalf of Griffin on Eurex, the German futures exchange. Despite this action, the bank is still facing millions in losses.

Finbarr O'Connell, partner at accountants Grant Thornton and joint liquidator to Griffin, said almost $5 million remained in the firm's client account in London.

Whether all of this was returned to traders depended on legal advice and their contracts, he said. The British Securities and Futures Authority, however, said it would encourage an accelearated interim payout if there were difficulties.

The affair has shocked many traders, who mistakenly believed that client money had been "segregated" into separate accounts at Griffin.