The CBI on Sunday asked the head of the Special Investigation Team of Kolkata Police that was probing the rape and murder at RG Kar Medical College and Hospital to give details of the procedure followed in registering the “unnatural death (UD)” case.

Sources in the central agency said Vidit Raj Bhundesh, the deputy commissioner of Kolkata Police’s detective department (special), who headed the SIT, met the CBI officers at the CGO Complex in Salt Lake on Sunday.

CBI sources said the queries to the deputy commissioner were related to the procedure followed by Kolkata Police in registering the “UD case”.

During a hearing of the case in the Supreme Court on Thursday, the division bench headed by the Chief Justice of India raised multiple questions on Kolkata Police’s alleged delay in registering a case. The state’s counsel, Kapil Sibal, refuted the charges and responded with a detailed timeline.

During the hearing, one of the judges on the bench asked whether the post-mortem was done without registering a UD case. He referred to a document that mentioned that the UD case was registered at 11.30pm.

“Just tell us at what time the post-mortem was performed?” the judge asked. Sibal responded: “Between 6.10pm and 7.10pm.” The judge said: “When a post-mortem is done, is it a case of UD? If not, why would a post-mortem be needed? Then why has the UD case registered at 23.30 hours?”

Sibal responded that “UD case (No. 861/24) was registered at 1.45pm”.

He later explained before the court that the UD case reference was mentioned in the requisition document of the judicial magistrate for the judicial inquest. The UD case reference was also mentioned in the post-mortem report, he said, reiterating that the judicial inquest or the post-mortem would not have been possible without registering a UD case.

The CBI officers on Sunday had a few queries on similar lines, sources said.

Several other members of the SIT, which investigated the rape and murder till Calcutta High Court handed the probe to the CBI, met officers of the central agency at the CGO Complex over the past few days.

“We will cooperate with them and help them in all possible ways,” one of the officers told Metro on Sunday.

He said some CBI officers are at times facing problems deciphering statements recorded in Bengali. “We are offering help in such cases,” the officer said.

The officer-in-charge of Tala police station, who had earlier been asked to meet the CBI officers, visited the CGO Complex again on Sunday. Sources said the central agency had sought some information related to the probe, which was shared with the CBI during the day.

Polygraph test

CBI officers on Sunday carried out a polygraph (lie-detection) test on two of the four junior doctors who were on night duty with the postgraduate trainee on the night she was raped and murdered.

Another four-member team from the agency went to Presidency jail and performed a polygraph test on Sanjay Roy, the only person arrested in the case.