Geneva  - Banks and financial institutions in Geneva have lost possibly some 5 billion Swiss francs (4.2 billion dollars) in their involvement with former Nasdaq chairman Bernard L Madoff who was arrested the day before in New York, a Swiss paper reported Saturday.

The Le Temps newspaper, without naming its sources, called the affair an "earthquake," and that a leading hedge fund, Union Bancaire Privée, had exposure of about 1 billion dollars.

The company declined to comment on the report.

A private bank, Benedict Hentsch, said on Friday it could lose up to 47 million dollars to the fraud, meaning about 5 per cent of the assets it manages.

There was also concern for private investors.

Madoff's business, Bernard L Madoff Investment Securities LLC, operated as an international market broker with brokers, banks and financial firms and had a separate investment advisory business for private clients.

The advisory business was kept secret by Madoff and served between 11 and 25 clients with 17.1 billion dollars under his management.

In admitting his wrongdoing to employees, Madoff said he had lost at least 50 million dollars on the scheme, in which he paid returns to investors using the principal received from other investors. (dpa)