In the early morning raids, 36 teams swooped down upon the residences of MLAs of Ranchi, Jamshedpur, Hazaribagh, Godda, Banka district and Giridih of Bihar, a CBI official told PTI.
The MLAs belong to ruling JMM, Ajsu party and opposition RJD and Congress, he said.
The sleuths are also raiding at a place in Kolkata, he said, adding a CBI team is also raiding the premises of one of the independent candidates who was in the fray in elections to the Upper House.
On April 21, the CBI had raided the premises of three MLAs, Vishnu Bhaiyya (JMM), K N Tripathy (Congress) and Suresh Paswan (RJD) and independent candidate and industrialist R K Agarwal and his kin.
The sleuths of the investigating agency had also seized the ballot box, which was used in the March 30 countermanded elections to Rajya Sabha as part of their probe, on April 21.
The agency has registered a case under section 171F (undue influence) and 188 of the Indian Penal Code (disobedience to an order lawfully promulgated by a public servant), days after the police and the Income Tax department seized Rs 2.15 crore from a vehicle allegedly belonging to a relative of an independent candidate on the outskirts of Ranchi on poll day.
The EC had conducted the fresh biennial elections on May 3 for the two RS seats.