Paul Careless, 43, who runs Brighton-based Surge Financial, which did the marketing for London Capital & Finance [LCF] was arrested last week.
It is the first arrest by the Serious Fraud Office since February when four men were questioned in connection with the collapse of the Eridge-based firm.
Commissions
LCF was setup by Tunbridge Wells businessman and former local Conservative party chairman, Simon Hume-Kendall.
Last month, the fraud squad froze assets belonging to Hume-Kendall and several other men, including Hadlow Down businessman Elten Barker, Spencer Golding from Crowborough and former LCF chief executive Andy Thomson.
Savers had thought money invested into LCF ‘mini-bonds’ were going to a range of start-ups, generating returns as high as 8 per cent, but in reality money went to a small number of companies in what administrators called ‘highly suspicious’ transactions.
Brighton-based Surge Marketing, was paid £57million for what they say was representative of the commissions paid in the sector.
Asked about the arrest, a spokesman for Mr Careless said: “Paul Careless has not been charged and he is not on bail.
“Surge was a third-party supplier of services used in relation to raising investment for LCF. It did not handle client money and had no involvement in the deployment of funds to borrowing companies.’