K D Biswal, they said, was arrested "red-handed" by a CBI team when he was allegedly accepting the bribe from the complainant, a civil works contractor.
Biswal is an assistant engineer at the premier All India Institute of Medical Sciences (AIIMS).
The CBI had lodged a case against Biswal for allegedly demanding Rs 19,500 as a quid pro quo ("something for something" in Latin) for clearing the bills of the contractor, a spokesperson of the probe agency said.