The accused also "extracted" Rs 1.11 crore from the boy's father during this period, police said.
"A distant relative of the developer promised to send his son to US for further studies in 2011 and instead of sending him abroad held him captive at Kolkata, Surat, Goa and Navi Mumbai and extracted money from the complainant builder from time-to-time," additional SP Vasai Division Yogesh Kumar told PTI.
No arrest has been made in the connection with the case so far, said the officer.