There are no reports of any casualties so far, Fire Brigade sources said.
Two people are feared trapped in the rubble and rescue efforts are going on, said authorities.
As many as 40 families were living in the building.
In April this year, an illegal under-construction building had collapsed in Thane's Shil Phata area, killing 74 people and leaving over 60 injured.
Image used for representational purpose only
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