"Builders Jamil Qureshi and Salim Shaikh were arrested from their hideouts today," Thane Police Commissioner K P Raghuvanshi told PTI.
Qureshi was nabbed from Uttar Pradesh, while Shaikh was apprehended from Thane, he said.
Police had registered a case of culpable homicide not amounting to murder against the builders, who were on the run since the incident.
The seven-storey unauthorised building at Shil Phata in Mumbra in the district had come down crashing in a heap on Thursday evening, in the worst tragedy of its kind in Maharashtra, and by the time rescue operations were called off on Saturday afternoon, 72 people were dead.
Image: Rescue operations in the Thane building collapse were called off on Saturday | Photograph: Sahil Salvi