Four people died after a two-storey building collapsed in Thakruli town in Thane district, officials said on Wednesday.
At least 12 fire engines have been rushed to the spot and 15 people were pulled out of the rubble of the three-decade old structure that collapsed late Tuesday.
The incident occurred around 10.15 p.m. on Tuesday night when the tenement, Matrukrupa, in Cholegaon area of the town.
At least 20 families residing in the structure are feared trapped in the debris.
Heavy rains, narrow approach and power breakdown hampered relief and rescue efforts and top police and civilian officials were present on the spot.