Tapan Kumar Deka's appointment as Intelligence Bureau, the domestic intelligence agency of the country, is a generational shift in the IB.

His predecessor, Arvinda Kumar, was a 1984 batch IPS officer and Deka is four batches junior to him. Not only that there are at least five more IPS officers in agency who are senior to him in his batch of 1988. He has also superceded, another senior officer, 1987 batch IPS officer AS Rajan, in the agency to be appointed as the IB chief.

Two more officers, who were senior to him, 1986 batch IPS officer Sheel Vardhan Singh and 1987 batch officer Swagat Das, have already been sent out of the agency. Singh was sent out in November last year to take charge as CISF chief and Das was made special secretary (internal security) in the ministry of home affairs, a couple of days back. There was one more officer in the IB of 1987 batch, Sunil Bansal, who went back to his parent cadre Orissa as chief of the state police in December last year.

Sources say Deka was handpicked by Union Home Minister Amit Shah to lead the IB. Besides him, the other officer in fray was AS Rajan, who was once considered a favourite because he had served in the Ahmedabad unit of IB as its chief but the home minister's preference tilted scales in favour of Deka.

After Nehchal Sandhu, Deka would be first IB chief to have background in the operations directorate of the IB where has served as deputy director and joint director before going to Guwahati as chief of IB local unit there.

The indication of rising stock of Deka came when he was given responsibility of Kashmir desk as special director amid rising violence after abrogation article 370 there. He impressed the home minister with his thorough work ethic.

But in comparison, in the external intelligence agency, Research and Analysis Wing, the government has persisted with the tried and tested Samant Goel, a 1984 batch IPS officer of Punjab cadre for another year. This is going to be the second extension for a year for Goel in R&AW.