The Income Tax (I-T) department on Sunday concluded raids on premises linked to former Union minister S M Krishna's businessman son-in-law V G Siddhartha, who is also founder-owner of Cafe Coffee Day, the country's largest coffee retail chain. A senior public relations official of the I-T department in Bengaluru confirmed that the department has detected over Rs 650 crore of undisclosed income linked to Siddhartha, after four days of raids.