Narendra Modi took the oath of office and secrecy of prime minister at Rashtrapati Bhavan.
President Droupadi Murmu administered the oath to Narendra Modi at Rashtrapati Bhavan.
As Modi took the oath, the crowds chanted "Modi Modi".
PM Modi became the second person in the history of India to hold the office of the prime minister for three successive terms.
The grand oath-taking ceremony, which was organised at the Rashtrapati Bhavan, also saw the presence of several foreign leaders and dignitaries.
Across the national capital, the security was strengthened and prohibitory orders were imposed. Delhi was declared a no-fly zone and three-layered security was implemented.