Sikkim Krantikari Morcha (SKM) president Prem Singh Tamang was sworn in as chief minister of the Himalayan state on Monday.
He was administered the oath of office and secrecy by Governor Lakshman Prasad Acharya at a function held in Paljor Stadium here.
Tamang, 56, became the chief minister for a second consecutive term.
The SKM returned to power in Sikkim by a landslide victory, winning 31 seats in the 32-member assembly.
The opposition Sikkim Democratic Front (SDF), which ruled the state for 25 years in a row till 2019, could manage only one seat.
