Former Madhya Pradesh police chief Rishi Kumar Shukla took charge as the new CBI director on Monday, with his first major challenge coming from Kolkata where the agency’s attempt to question city top cop Rajeev Kumar triggered a confrontation between Mamata Banerjee and the Centre. A 1983 batch IPS officer of the Madhya Pradesh cadre, 59-year-old Shukla was appointed the 28th Director General of Police (DGP) of Madhya Pradesh on June 30, 2016. He was shifted to the post of Police Housing Corporation chief last week by the new Congress regime in the heartland state.