John Steele, 38, was found by prison guards hanging in his cell on Tuesday, four days after he was remanded in custody.
Steele, who had lived near Paris for some years, was believed to be behind a scheme which took more than £1 million in loans from French banks.
A Foreign Office spokesman said: "We are aware of the death of a British national in France on 21 May and we stand ready to provide consular assistance."
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