CBI or Central Bureau of Investigation is facing its worst crisis. The top two officers, director Alok Verma and his deputy Rakesh Asthana, were sent on compulsory leave. The offices of both Alok Verma and Rakesh Asthana have been sealed by the agency in an alleged bribery case. M Nageswara Rao took temporary charge of the CBI in the early hours of Wednesday.Nageswar Rao, an Indian Police Service (IPS) officer of the 1986 batch, joined the CBI in 2016. He was the joint director before his stunning leap as interim director. Mr Rao is reputed to be a tough cop and decorated administrator. He is from Warangal in Telangana. A chemistry post-graduate from Osmania University, he did research in Madras IIT before joining the IPS.