The CBI on Sunday conducted searches on the premises of former principal of RG Kar Medical College and Hospital Sandip Ghosh, ex-medical superintendent Sanjay Vashisth and 13 others in and around Kolkata in connection with their probe into alleged financial irregularities at the institute, officials said. The anti-corruption unit of the Central Bureau of Investigation (CBI) also searched the residences and offices of those engaged in supplying materials for the management and care of patients. A postgraduate trainee woman doctor was allegedly raped and murdered in the seminar hall of the hospital on August 9, following which a Kolkata Police civic volunteer was arrested.