Two teams of the Central Bureau of Investigation interrogated Sandip Ghosh, the former principal of RG Kar Medical College and Hospital, once at Nizam Palace and then at the CGO complex in Salt Lake on Monday.

Ghosh was questioned about the rape and murder case at the CGO complex while he was grilled for the alleged financial irregularities at RG Kar at the CBI’s Nizam Palace office.

Debasish Som, who is engaged as a demonstrator at the forensic medicine department of RG Kar Medical College and Hospital, was also questioned by two separate teams.

Till Monday Som’s name had emerged only in the alleged financial irregularities. However, on Monday, he was summoned to the CGO complex.

The move came a few hours after a purported video was circulated showing several people, including Som, standing inside the seminar hall where the young doctor’s body was found on August 9.

The CBI team probing the rape and murder also called some officers of Tala police station to the CGO complex seeking information and assistance on certain matters, sources in the central agency said.

An officer of the rank of assistant commissioner of the Kolkata Police was also called at the CGO complex.

The central agency took over the probe of the rape and murder on August 13 but is yet to make any arrests in this case. The only person arrested in connection with the rape and murder was a Kolkata Police civic volunteer who had been identified and picked up by the Kolkata Police while the case was still with them.

The central agency on Sunday had sought the details of the procedure followed by the police in registering the unnatural death case.

Deputy commissioner, detective-department (special), Vidit Raj Bhundesh, who was heading the special investigation team of the Kolkata Police that was probing the case, met CBI officers on Sunday to clarify doubts.