The Azad Maidan police, probing the CST-DN Road bridge collapse case, in which six people died, told the Esplanade court on Tuesday that Neeraj Desai, the arrested director of the firm that audited the bridge for structural safety, had subcontracted the work to a Vadodara firm, Geo Dynamics. It has also emerged that there was a long delay in the structural audit report of 80 bridges by the firm DD Desai's Associate Engineering Consultants. The work order was issued by the BMC to the firm in October 2016 with the duration stated as eight months. The firm submitted the final report in August 2018."He (Desai) was supposed to audit the bridge and submit the report to the BMC. During police investigation, it transpired that non-destructive test on the bridge was carried out by Geo Dynamics and its report was part of the main audit report," said a police officer on Tuesday. "The auditing of a bridge is a sensitive issue and this man (Desai) was given the work for dozens of bridges."An official from Geo Dynamics told TOI, "Our work was limited to the extent of testing some piles and columns of the staircase. We were not associated with the entire job of auditing the structure. It wasn't that the work was subcontracted to us in anyway."Emphasizing that the firm had limited involvement in the audit, he said, "The piles and columns tested by us are still intact. Besides, we are only a testing company and not a consultancy or auditing company. The locations we were asked to check by Desai's firm were tested."The official added that the firm also tested columns of other bridges suggested by Desai. The police said they may summon the firm's office bearers. An officer said experts will be hired to help investigators understand the audit reports. "What all he (Desai) says needs to be verified," said DCP Abhishek Trimukhe.On the audit report's delay, Desai's lawyer said in court that it occurred due to a delay in obtaining certain testing equipment sought by Desai's firm. "The initial inspection of the FOB was done in December 2016. There was back and forth with the civic body over the report, which added to the delay in its submission."