Digambar Kamat, who engineered the downfall of the Bharatiya Janata Party government in 2005 and then joined the Congress, was sworn in on Friday as the 19th chief minister of Goa.
Goa Congress chief Ravi Naik, who was in the race for chief ministership, NCP's Jose Filipe D'souza and Maharashtravadi Gomantak Party's Ramkrishna alias Sudin Dhavalikar were also sworn in as cabinet ministers at a ceremony in Raj Bhavan.
Governor S C Jamir administered the oath of office and secrecy to Kamat and three ministers.
54-year-old Kamat, who was the power minister in the previous government led by Pratapsinh Rane, was the compromise choice for the post after opinion among Congress MLAs were sharply divided on whether Rane or Naik should become the chief minister.
Kamat had played a key role in engineering the downfall of the BJP-led government in Goa headed by Manohar Parikkar in 2005.
He then joined Congress and became a minister.
Congress, which won 16 seats in the June 2 Assembly polls, and NCP formed the government in the state backed by two independents and Maharashtrawadi Gomantak Party which has two MLAs.
The Goa Assembly has a strength of 40.