Jhulan Das, wife of the patient Ratan Das, 53, a small-time trader of Ampi Bazaar in southern Tripura, filed a complaint Saturday in this regard with the police and the state health minister.
In her complaint, she said: "Following the advice of senior doctors, my husband was admitted to the Gobinda Ballav Pant Medical College and Hospital last week. He was to undergo a biopsy of his mouth. But the doctors conducted surgery on his lower abdomen and urethra instead."
She also said in her complaint: "I learnt about the wrong operation upon my husband, when he was screaming in his hospital bed on Saturday."
"I asked the doctor why my husband's lower abdomen was operated upon. But the doctors on duty threatened me to remain silent or face dire consequences."
When contacted, doctors at the medical college told reporters the patient has problems in his lower abdomen and urethra also.
But Jhulan Das rejected the doctors' claim.
Speaking on condition of anonymity, sources at the medical college said another patient named Ratan Das with abdomen and urethra-related problems was admitted to the hospital.
The East Kotwali police is probing the matter.
J. Jayalalithaa passes away: Her life in pictures
Photos: Shah Rukh Khan, Deepika Padukone, Alia Bhatt at an awards show
Photos: Big B, Iulia Vantur at Himesh Reshammiya's album launch
Photos: Aamir Khan with 'Dangal' actresses at fashion show
Spotted: Twinkle Khanna, Shriya Saran at an event in Mumbai