(CNN) Millions of people across India have been placed under lockdown until the end of the month as efforts to halt the spread of the novel coronavirus in the country intensify.

Residents living in 75 districts across the country, including in major cities such as the capital New Delhi, Mumbai, Bangalore, Chennai, Hyderabad, and Kolkata have been placed under travel, work and movement restrictions until March 31.

India -- the world's second most populous country -- has 415 cases of the coronavirus, including seven deaths, according to the Ministry of Health and Family Welfare. A sudden rise in cases has led to growing concerns over the country's capacity to test for the virus and that a major outbreak on the scale seen in Europe -- the pandemic's new epicenter -- will spread in the country.

Dr. Balram Bhargava, director-general of the Indian Council of Medical Research, said that India has conducted 5,000 tests in the past week and a total of 15,000 so far. There are 111 labs operational with a per week testing capacity of 60,000 to 70,000 and around 60 more private labs are in the process of being approved to further increase testing capacity, according to Bhargava.

The decision to lock down parts of the country comes after India launched the world's biggest exercise in social distancing on Sunday, with the nation's 1.3 billion people asked to observe a self-imposed quarantine for 14 hours.

From 7 a.m. to 9 p.m. on Sunday, offices and businesses shut, people stayed inside their homes, and the usually busy streets, markets and highways were eerily empty across the nation. In a display of public solidarity expressing thanks to the nation's healthcare workers, people across India stood in their doorways and on balconies applauding, ringing bells and blowing conch shells, following similar scenes days prior in Italy and Spain. Read more at CNN