According to the police, the arrested persons had helped the Patna blasts culprits to hide in the city after the blasts.
"NIA's team interrogated the eight suspected SIMI operatives," DGP Ramniwas told PTI.
NIA questioned them about whereabouts of the four absconding suspects, he said, not ruling out the possibility of NIA taking the custody of the arrested SIMI operatives.
Umer Sidhhiqui, Sheikh Ajijullah, Moinuddin Kureshi, Abdul Wahid, Sheikh Habib Ulla, Roshan Sheikh, Md Aziz and Hayat Khan were arrested from various parts of Raipur last week.
According to the DGP, Haider Ali alias Abdullah, prime accused of Patna blasts case, and other suspects were in contact with Umer Siddhiqui and Abdul Wahid, who helped Abdullah get a rented house in Sanjay Nagar area of Raipur.
Moinuddin rented his house in Sanjay Nagar area to Abdullah and his associates. But they had disappeared by the time the police raided the house.
Sheik Habib Ulla, Hayat Khan and Roshan had attended a meeting of SIMI - now banned - at Barnawapara forests, around 100km away from Raipur some years ago. They all have been booked under Prevention of Unlawful Activities Act, 1968.