BJP president Amit Shah and police officers DG Vanzara, Rajkumar Pandiyan and Dinesh MN were "principal conspirators" in the alleged fake encounter killing of Sohrabuddin case witness Tulsiram Prajapati, a police officer told a Mumbai court on Wednesday. Sandeep Tamgadge, an Indian Police Service officer, investigated the Tulsiram Prajapati and Sohrabuddin cases from April 2012. Mr Tamgade told the trial court that he interrogated Amit Shah as well as Gulabchand Kataria, current home minister of Rajasthan and there were "incriminating" statements.