Three persons were Thursday arrested on the charge of culpable homicide not amounting to murder in connection with the collapse of a wall at Kalyan in the district, which had claimed three lives, police said.
Two others have also been booked in this connection, but are yet to be arrested, they said.
According to officials, the compound wall of an Urdu school near Durgadi fort had fallen on an adjacent chawl in the wee hours of Tuesday, killing three persons, including a three-year-old boy.
"Three chawl owners, identified as Salman Moulavi, Salim Moulavi and Javed Moulavi, were arrested in this connection, while two others were booked," an official of Bazarpeth police station said.
The five accused had constructed the chawls without obtaining necessary permissions from the Kalyan Dombivli Municipal Corporation (KDMC) and rented out the houses to families, he said.
The accused have been booked under IPC section 304 (culpable homicide not amounting to murder) and others, the official said.