Rescuers who pulled out 67 people alive from the rubble were clearing the crumbled concrete and twisted metal rods a day after the collapse in the crowded area of the eastern Indian city.
There is no possibility of finding anyone else alive, according to SS Guleria, deputy inspector general of the India’s National Disaster Response Force.
The five detained employees worked for Hyderabad-based IVRCL Infrastructure, which was contracted in 2007 to build the overpass. Police also sealed the firm’s Kolkata office.
The officials are being questioned over possible culpable homicide, an offence punishable by life imprisonment, and criminal breach of trust, which carries a prison sentence of up to seven years.
The partially constructed overpass had spanned nearly the width of the street and was designed to ease traffic through the densely crowded Bara Bazaar area in the capital of the east Indian state of West Bengal.
Within hours of concrete being poured into a framework of steel girders on Thursday, about 300ft of the overpass collapsed.