The death toll in a four-storey building's collapse here the day before mounted to 46, with 11 more bodies being recovered from the debris Saturday, officials said.
Thirty-two people were injured, including four critically, and the search continues for rescuing a few more people who remain trapped under the debris, the BMC Disaster Control department said.
Among the victims in the tragedy was 31-year journalist with Sakal newspaper, Yogesh Pawar, and his father Anant Pawar, a civic employee.
Situated near the Dockyard Road, south Mumbai, the 33-year-old building served as civic employees' staff quarters.
Housing around 21 families, it suddenly collapsed around 5.45 a.m. Friday, catching majority of the sleeping residents unawares, the official added.
Moving to fix responsibility for the state's second worst building crash tragedy of this year, Mumbai police arrested the proprietor of a marquee decoration firm who had allegedly carried out illegal modifications on the ground floor of the doomed building.
Suspected renovation and alterations carried out in his office-cum-godown may have led to further weakening of the dilapidated structure and hastened its collapse.
On a complaint by a civic official, Sewree police nabbed Ashokkumar J. Mehta of Mamamiya Decorators under various charges pertaining to culpable homicide not amounting to murder, according to Additional Police Commissionner (South) Krishna Prakash. He has been sent to three days police custody.
A few years ago, the 28-flat building, of which seven were unoccupied, and a ground floor warehouse leased to a marquee decorating firm, was declared "extremely dilapidated".
Last month, it was surveyed by a BMC team which recommended urgent repairs after shifting the families living there.
Chief Minister Prithviraj Chavan announced a compensation of Rs.100,000 and city Mayor Sunil Prabhu announced a compensation of Rs.200,000 to the families of each of the deceased.
This is the seventh major building collapse in Mumbai metropolitan and neighbouring areas in the past six months.
In the worst disaster in the state's history, 75 lives were lost when a building collapsed April in Mumbra's Lucky Compound.
In June, four more buildings crashed - in Mahim (10 dead), Mumbra (10 dead), Dahisar (seven dead) and Bhiwandi (three dead).
Last Saturday, Banoo Apartments (Bhiwandi) turned to rubble but without fatalities as over a 100 occupants managed to run to safety before it crashed.