Hospitals and clinics across India turned away patients except for emergency cases on Saturday as medical professionals started a 24-hour shutdown in protest against the brutal rape and murder of a doctor in the eastern city of Kolkata.

More than one million doctors were expected to join the strike, paralysing medical services across the world’s most populous nation. Hospitals said faculty staff from medical colleges had been pressed into service for emergency cases, Reuters reported.

The strike, which began at 6 a.m. (0030 GMT), cut off access to elective medical procedures and out-patient consultations, according to a statement by the Indian Medical Association.

A 31-year old trainee doctor was raped and murdered last week inside a medical college in Kolkata where she worked, triggering nationwide protests among doctors and drawing parallels to the notorious gang rape and murder of a 23-year-old student on a moving bus in New Delhi in 2012.

Outside the RG Kar Medical College, where the crime took place, a heavy police presence was seen on Saturday while the hospital premises were deserted, according to the ANI news agency.

Mamata Banerjee, the chief minister of West Bengal, which includes Kolkata, has backed the protests across the state, demanding the investigation be fast tracked and the guilty be punished in the strongest way possible.

A large number of private clinics and diagnostic centres remained closed in Kolkata on Saturday.

Dr Sandip Saha, a private paediatrician in the city, told Reuters that he will not attend to patients except in the case of emergencies.

In Odisha state, patients were queuing up and senior doctors were trying to manage the rush, Dr. Prabhas Ranjan Tripathy, additional medical superintendent of All India Institute of Medical Sciences in the city of Bhubaneswar, told Reuters,

“Resident doctors are on full strike, and because of that, the pressure is mounting on all faculty members, which means senior doctors,” he said.

Patients queued up at hospitals, some unaware that the agitation would not allow them to get medical attention.

“I have spent five hundred rupees on travel to come here. I have paralysis and a burning sensation in my feet, head, and other parts of my body,” a patient at SCB Medical College Hospital at Cuttack in Odisha told a local television channel.

“We were not aware of the strike. What can we do? We have to return home.”

Anger at the failure of tough laws to deter a rising tide of violence against women has fuelled protests by doctors and women’s groups.

“Women form the majority of our profession in this country. Time and again, we have asked for safety for them,” IMA President R. V. Asokan told Reuters on Friday.

India’s Central Bureau of Investigation, the agency investigating the rape and murder, has summoned a number of medical students from the RG Kar college to ascertain the circumstances of the crime, according to a police source in Kolkata.

The CBI also questioned the principal of the hospital on Friday, the police source said.