Governor R S Mooshahary administered the oath of office and secrecy to Lapang at a programme in Raj Bhavan. Lapang heads an alliance, Meghalaya United Alliance, comprising the Congress and a regional party, United Democratic Party.
The alliance has 37 Members of Legislative Assembly -- 26 from the Congress, nine from UDP and two Independents -- in the 60-member house which now has an effective strength of 55, following resignation of one UDP MLA and disqualification of four others.
Meghalaya was under President's rule since March 18 after the governor reported that there was a 'breakdown of constitutional machinery.'
Besides Lapang, Deputy Chief Minister Mukul Sangma (Congress) and five other ministers -- R C Laloo, M M Dangoo, Ampareen Lyngdoh (all Congress), J A Lyngdoh (UDP) and A T Mondol (Ind) -- were also sworn-in.
Ampareen Lyndog, who joined the Congress from UDP last month, is not a member of the house now and has to be elected within six months.