The people are said to have been “providing financial advice when not authorised to do so and making misleading statements to investors.”
The individuals were arrested by West Midlands Police after obtaining search warrants on three West Midlands premises.
No names have been given and nobody has yet been charged.
The FSA investigation is continuing and it cannot comment any further on the case.
According to FSA rules, individuals must be authorised to provide financial advice or arrange investment deals under the Financial Services and Markets Act 2000.
Failure to be authorised can be punished with fines and two years in prison and making misleading or deceptive statements can be punishable with fines and up to seven years in prison.