He told reporters he was not involved in the financial dealings of the Saradha's media ventures, but was still being harassed and mentally tortured in police custody.
Ghosh was brought to Alipurduar in Jalpaiguri district on Tuesday. The next day he was produced in a court at Alipurduar and sent to judicial custody.
On Friday, he was produced before a Jalpaiguri court in connection with an FIR filed against him at Bhaktinagar police station. The police requested his 10-day remand, but the court sanctioned the eight-day custody.
Ghosh immediately started hunger strike on the ground that sending him in police remand repeatedly amounted to harassment.
Talking to reporters on Saturday, Ghosh said a "genuine investigation" into the scam should start from Netaji Indoor Stadium.
Ghosh had earlier threatened to disclose names if he was arrested and demanded an inquiry by his party saying he had much to tell the leadership.
Asked if he feared for his life, he said, "This (investigation) is nothing but a ploy to kill me."
The Saradha scam, in which lakhs of investors were duped, came to light in April last year and group chairman Sudipta Sen was arrested along with two others from Sonmarg in Jammu and Kashmir.