Indian Railway Minister Kumar Bansal resigned from his post after bribing his relatives.
Bansal said that the scandal made a resignation to Prime Minister Manmohan Singh in a statement to journalists after broadcasting on state television.
Opposition leaders claimed that Bansal's relatives had been enriched by using their relationship with the minister.
Federal investigators announced that 166 people were arrested, including minister employee Maheş Kumar, who allegedly blamed Bansal's nephew, Vijay Singla, for the run-down job at the railway administration.
Public television also announced that the Congress Party asked for Justice Minister Ashwini Kumar to resign after the upper court strongly opposed the rewriting of the investigation into the piece coal deal agreement.
The agreement, which includes the sale of lump coal to private companies without tendering in India, is being investigated by federal authorities.