New Delhi: Gitantajali Group Promoter Mehul Choksi, accused of involvement in a over Rs 12,000 crore fraud against the Punjab National Bank along with nephew celebrity jeweller Nirav Modi, has written a letter to the Central Bureau of Investigation (CBI) alleging abuse of due process. He also told the probe agency that it is "impossible" for him to return to India since his passport has been suspended. As one of the key accused in what has been dubbed the biggest fraud in India's banking history, Mr Choksi, along with Mr Modi, has been summoned by the Enforcement Directorate. In the letter dated March 7, he said that the investigating agencies have been acting with pre-determined minds and interfering with the course of justice. Mr Choksi further said that the seizure of his assets, bank accounts and shutdown of his offices have cause prejudice against him.