The Autoriteit Financiele Markten, the Dutch financial services regulator, has voiced concern over the lack of transparency of hedge funds.

A spokesman for the Dutch regulator said: "The AFM identifies a number of risks attached to the rapid rise of hedge funds. Although the AFM sees no pressing need for more regulation or tighter supervision, a follow-up investigation is to be carried out at a number of institutions in order to obtain more information about Dutch market practices."