Of the 59 injured, 36 have been admitted to hospitals in Thane, Kalwa and Mumbra. The seriously injured have been shifted to JJ and Sion Hospitals in Mumbai.
At the collapse site, a survivor identified as Shabnam told reporters that she had received a call on her mobile phone from a young teacher around 3pm on Friday saying she was trapped alongwith six-seven students, but lost contact thereafter.
The fate of the teacher and students is still not known.
National Disaster Response Force, alongwith local police and civic administration, was engaged in rescue operations.
The illegal structure, which was under-construction, collapsed on Thursday.