Anup Wadhawan, the Joint Secretary with the Department of Financial Services, assumed concurrent charge as Chairman of the Pension Fund Regulatory & Development Authority (PFRDA) on Wednesday to fill the vacancy created by the abrupt resignation of Yogesh Agarwal.

Mr. Agarwal stepped down as chairman of the PFRDA, years before the previously scheduled end of his five-year term in 2015.

While the PFRDA remained tight-lipped on the reasons for Mr. Agarwal's resignation, reports suggest that a finance ministry investigation into appointments made by Mr. Agarwal prompted the unprecedented move.

The finance ministry is probing charges that Mr. Agarwal tweaked recruitment norms to give preferential treatment to employees of state-run lender IDBI, of which Mr. Agarwal was chairman before moving to the pension regulator.

Currently, PFRDA has a total of 51 senior employees, with ranks ranging from general assistant to executive director. Nearly a quarter of these employees are from IDBI.

Mr. Wadhawan will act as interim chairman of the PFRDA till the authorities find a new boss for the pension regulator, which became a statutory body after Parliament cleared the PFRDA Bill in the past monsoon session.