Under Secretary Sanjay Mehta, section officers Hemant and Vijay Pal and assistant section officers R K Arora and Mahendra Singh have been booked for alleged irregularities in the payment of over Rs 18 lakh, officials said.
The CBI has taken action on the basis of a complaint from the DoPT.
Mehta was placed under suspension after irregularities were found in payments, they said.