The woman’s body was found in a classroom at the state-run R G Kar Medical College and Hospital on Aug 9. Other doctors stayed off work for weeks to demand justice for her and better security at public hospitals.

Defendant Sanjay Roy said in November that he was “completely innocent” and was being framed.

Roy’s lawyers could not immediately be reached for comment on the verdict. They had argued there were glaring discrepancies in the investigation and forensic examination reports.

Judge Anirban Das said the sentence, to be announced on Monday, would range from life in prison to the death penalty.

The parents of the victim, who cannot be named under Indian law, expressed dissatisfaction with the probe, saying the crime could not have been committed by just one person.

“Our daughter could not have met such a horrific end by a single man. We will remain in pain and agony until all the culprits are punished,” her father said.

India’s federal police, who investigated the case, described the crime as “rarest of rare” during the trial and sought the death penalty for Roy.

Several doctors chanted slogans in solidarity with the victim outside the court. Dr Aniket Mahato, a spokesperson for the junior doctors, said street protests would continue “until justice is done”.

More than 200 armed police personnel were deployed in anticipation of the verdict as Roy was brought to court in a police car.

The investigation cited 128 witnesses– 51 of whom were examined during the trial, which began on Nov 11, and was fast-tracked to conclude swiftly, according to court sources.

Police also charged the officer heading the local police station at the time of the crime and the then-head of the hospital with destruction of the crime scene and tampering with evidence.

The police officer is out on bail while the former head of the hospital remains in detention in connection with a separate case of financial irregularities at the hospital.