Those detained since last night are - Assistant Municipal Commissioner Babasaheb Andale, police constable S Sayeed and NCP Corporator representing the ward, Hira Patil, they said.
Yesterday, police had arrested developers - Jamil Qureshi and Salim Shaikh - involved in the construction of the illegal seven-storey building, which collapsed in Thane district on Thursday.
Suspended Deputy Municipal Commissioner Deepak Chavan was also arrested in connection with the building collapse case yesterday, police said.
Civic authorities yesterday pulled down some godowns in the vicinity and two more such illegal buildings which had come up near the ill-fated building at Shil Phata area in Mumbra township of Thane district that crashed on Thursday.