The discovery prompted the government to swing into action late night yesterday and transfer the senior superintendent of police (SSP) of CM Adityanath's high-profile home district.
SSP Gorakhpur R P Pandey was replaced by SSP Special Task Force (STF) Amit Kumar Pathak.
"From mobile tower location and voice record details, the caller was traced. District jail inmate Sanjay Yadav had made the call to the surgeon. A raid was conducted in the jail last night and the mobile and sim card were recovered," SP City Vinay Singh said.
Dr S S Shahi, who runs a private hospital in Gorakhpur, had received calls on his mobile phone demanding Rs 20 lakh on June 28 and 29.
Yadav threatened him with dire consequences if he failed to pay, he said.
Police security was provided to the doctor after the call.
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