An eerie silence descended on the country as millions of Indians stayed indoors on Sunday following a call given by Prime Minister Narendra Modi for a “people’s curfew” to break the transmission chain of the novel coronavirus.

Traffic was negligible as people struggled in some places to find transport from airports. Trains and public buses also did not ply.

Just before 5 p.m., sirens sounded in several cities and people came out onto the roads and balconies clapping their hands and banging steel plates to express gratitude to those providing essential services during this crisis. In many places, conch shells sounded as people milled around.

In a series of tweets, Mr. Modi thanked the people for adhering to his call, but warned against any celebration when it came to an end at 9 p.m. on Sunday night. “Don’t treat this as a success. This is the beginning of a long battle,” Mr. Modi said.

Appealing to the people to adhere to the new restrictions being imposed by the Centre and the State governments, Mr. Modi said people should not move out of their houses in the 80 districts where a “lockdown” had been declared. “Even in other parts of the country [where there was no lockdown] people should stir out of their houses only when necessary,” he added.

Union Health Minister Harsh Vardhan warned that anti-social elements were “spreading misinformation that after #JanataCurfew ends, the deadly virus will be wished away”. “This is false & an attempt to mislead the public.”