Five more locations, including residences of PWD officials and other private persons, are also being searched, they said.
Jain is already facing probe in a case pertaining to money laundering.
The PWD minister, in a tweet, confirmed that the Central agency was carrying out searches at his residence.
The agency had registered a preliminary enquiry into the hiring of 24 architects for a creative wing of the PWD through an agency, which reportedly lacked any prior experience, the officials added.