Six persons were arrested on Wednesday in connection with the collapse of an under-construction flyover leading to the death of two persons seven months ago.

The six men, included two employees of Gammon India Ltd [Get Quote], the main contractor, two officers of Hyderabad metro water supply and sewerage board (HMWWSB) and an equal number of staffers of a consultant firm.

While T N V Satya [Images] Ratnaji and Sanjay Bhattacharya of Gammon India failed to test the soil-bearing capacity of the earth, the HMWWSB employees filled up the excavated trenches for laying the 800 mm pipe line with loose soil instead of stone quarry dust as per standard procedure, an official release said.

The HMWWSB officers are M Dharma Reddy, Deputy General Manager, and M Rajesh, Manager (engineering), R S Praveen Kumar, Deputy Commissioner of Police (detective department), said.

Two other arrested are B S R Laxman and G S N Madhusudhan Rao of Tanikella Integrated consultants.

A five-member technical expert committee constituted to probe into the incident found that the accident was caused due to the negligence on the part of the officials who were on supervisory duty.

Eight pre-cast cement segments of the flyover at busy Punjagutta junction collapsed resulting in the death of two persons on September 9 last year.