The CBI has sent a letter to West Bengal Health Secretary NS Nigam asking him to furnish details about why officials, allegedly involved in the RG Kar Hospital corruption case, are still holding key positions at the medical establishment, a source said on Wednesday.

The Calcutta High Court on August 23 ordered the transfer of the probe into the alleged financial irregularities at the hospital from a state-constituted Special Investigation Team (SIT) to the central agency.

The CBI is also probing into the alleged rape and murder of an on-duty postgraduate trainee inside the hospital on August 9.

In the letter to Nigam, the agency has questioned why two doctors -- Debasish Som and Sujata Ghosh -- were still holding their respective positions.

Som is the former Head of the Forensic Department of RG Kar Hospital and is currently holding the position of a 'Demonstrator' at the Forensic Medicine and Toxicology (FMT), the hospital website said.

Sujata Ghosh is an Associate Professor of the Anaesthesiology department.

"These people were very very close to the arrested former principal of RG Kar hospital Sandip Ghosh. There is evidence of that," a CBI officer told PTI.

The CBI on September 2 arrested Sandip Ghosh and three others in connection with the alleged financial misconduct at the hospital.

CBI officers have grilled Som several times as well as conducted search operations at his residence and office in connection with their probe.

RG Kar Medical College and Hospital's former principal Sandip Ghosh and suspended police officer Abhijit Mondal have been arrested in the financial scam at the hospital.

Incidentally, the junior doctors on hunger strike since October 5 are demanding, among others, the removal of Nigam from the post of health secretary.

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