Photo/Illutration A passenger walks past railway tracks at the deserted New Delhi Railway station during a lockdown amid concerns over the spread of the new coronavirus, in New Delhi on March 23. (AP Photo)

NEW DELHI--India’s colossal passenger railway system has come to a halt as officials take emergency measures to keep the coronavirus pandemic from spreading in the country of 1.3 billion.

The railway system is often described as India’s lifeline, transporting 23 million people across the vast subcontinent each day, some 8.4 billion passengers each year.

India’s rail network, the world’s fourth largest, operates more than 12,100 trains carrying passengers and cargo along 67,415 kilometers of track. With more than 1.2 million employees, it is the country’s largest employer.

The lifeline was cut Sunday, leaving hundreds of people stranded at railway stations, hoping to be carried onward by buses or taxis that appeared unlikely to arrive.

The New Delhi Railway Station--usually populated 24 hours a day with railway staff, shops selling snacks and newspapers, passengers crammed into waiting rooms and indigent people sleeping on the platform--was barren.

As local governments tightened restrictions on movement, migrant workers hauling backpacks swarmed overcrowded trains across many Indian cities, an exodus among panic-stricken day laborers that sparked fears the virus could spread to the countryside.

Even more drastic measures have followed.

Prime Minister Narendra Modi announced a nationwide “total lockdown” for 21 days starting Wednesday, ordering one-fifth of the world’s population to stay in place.

Health officials have reported 512 cases of COVID-19, the respiratory disease caused by the new coronavirus, and at least nine deaths.

From India’s first documented case of infection, it took 50 days for the total caseload to cross 200. In the past five days, the number of cases has crossed 500.