The Supreme Court on Monday voiced concern over the absence of a key document that was needed for the postmortem of the medic raped and murdered at the RG Kar Medical College in Kolkata, and asked the CBI to investigate into it.

The top court also directed the protesting resident doctors in West Bengal to resume work by 5 pm on Tuesday and said no adverse action shall be taken against them on resumption of work.

The court passed the direction after the West Bengal government assured it that no action, including punitive transfers, shall be taken against the protesting doctors on resumption of work.

A bench headed by Chief Justice D Y Chandrachud said there was no reference of the 'challan' (document) used, and sought an answer from the CBI and the West Bengal government.

"Where is the challan of the body when it was handed over for postmortem? the bench also comprising Justices J B Pardiwala and Manoj Misra said.

Solicitor General Tushar Mehta, appearing for the CBI, informed the bench that the challan was not part of their records

Senior advocate Kapil Sibal, appearing for the West Bengal government, told the bench that he could not find the document immediately and would get back to the court on this question.

The court also flagged the at least a 14-hour delay by Kolkata Police in registering FIR in rape and murder incident.

The top court directed the CBI to submit a fresh report by September 17 on the probe in the case.

The apex court also directed immediate removal of photographs of the victim from all social media platforms to protect the dignity and privacy of the deceased.

On the issue of security of medical institutions in the state, the Supreme Court said "All DMs, SPs in West Bengal to take stock of situation to ensure safety, security of government medical colleges".

Earlier in the day, the court perused the report filed in a sealed cover by the Solicitor General.

"A status report has been filed by CBI, it appears that investigation is in progress, we direct the CBI to file fresh status report...We don't want to guide the CBI on its investigation," the bench said.

Mehta told the bench that the probe agency has decided to send forensic samples to AIIMS for further investigation.

The apex court also directed a senior officer of the West Bengal government's Home department and a senior CISF officer to ensure all three companies of the CISF, which are deputed for security at the RG Kar Hospital, are given accommodation.

It also directed that all requisition, security gadgets needed by the CISF should be handed over to it today.

The matter is posted for next hearing on September 17.

At the outset, the West Bengal government told the top court that 23 people have died as doctors are on strike protesting the rape and murder of the postgraduate medic.

Sibal submitted a status report filed by the state health department.

"A status report has been filed. The state health department has filed a report. Tweny-three people have died as doctors are on strike," Sibal told the bench.

On August 22, the apex court had tore into the Kolkata Police over the delay in registering the unnatural death of the woman doctor, calling it "extremely disturbing", and questioned the sequence of events and the timing of its procedural formalities.

The top court had earlier constituted a 10-member National Task Force (NTF) to formulate a protocol for ensuring the safety and security of doctors and other health care professionals.

Terming the incident as "horrific", the apex court had excoriated the state government over the delay in filing the FIR and allowing thousands of people to vandalise the state-run facility.

The alleged rape and murder of the junior doctor in a seminar hall of the state-run hospital has sparked nationwide protests.

The medic's body with severe injury marks was found inside the seminar hall of the hospital's chest department on August 9. A civic volunteer was arrested by the Kolkata Police in connection with the case the following day.

On August 13, the Calcutta High Court ordered the transfer of the probe from the Kolkata Police to the CBI, which started its investigation on August 14.