All the three accused were living in Mumbai and were involved in the racket for quite some time, the officer added.
A police team visited the area to collect evidence in the case when locals started protesting with some of them 'offering' money to the officials, alleging that they were trying to shield the accused.
The incident happened at around noon on Sunday when a man barged into the flat in Beliaghata police station area, an officer said.
The woman has been admitted to Sagore Dutta Hospital with grievous injuries and the man arrested, police said.
Personnel of Kolkata Police DGM, along with sleuths of a local police station and fire department, tried to fish out Sarkar's body but even after hours of attempts they failed to recover it.
The doctor who was visiting the home of a woman for diagnosis was surrounded by three youths who took pictures of him with the woman and later used it to extort money from him.