The Central Bureau of Investigation (CBI) on Thursday continued to question Sandip Ghosh, the former principal of state-run R G Kar Medical College and Hospital, in connection with its probe into the alleged rape and murder of a medic, an official said.

Ghosh appeared for questioning before the central agency for the 13th consecutive day.

"Ghosh appeared before our sleuths for questioning," an official at the central agency said.

According to sources, the former principal of the state-run hospital, where the body of the trainee doctor was recovered on August 9, has already been questioned by the CBI for over 130 hours.

Following orders of the Calcutta High Court, the CBI took over the investigation into the alleged rape and murder of the postgraduate trainee doctor of the state-run hospital, from Kolkata Police.

A civic volunteer Sanjoy Roy was arrested by Kolkata Police in connection with the case.

Both Ghosh and Roy were among those who have undergone a polygraph test as part of the investigation process.

The CBI has named Ghosh in the FIR the agency has filed in connection with its probe into the alleged financial irregularities at the hospital during his tenure.

The central agency had, on August 25, conducted a day-long search operation at Ghosh's Beliaghata residence in Calcutta in connection with the corruption cases.

The Enforcement Directorate has also filed a money laundering case to probe alleged financial irregularities at the RG Kar Medical College and Hospital during the tenure of its former principal and some others, official sources said.

Unabated protests against the death of the doctor continue to rock the state and elsewhere in the country.

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