The Ghaziabad police on Friday arrested a supervisor of the contractor firm that was laying sewer lines in connection with Thursday's five deaths near Krishna Kunj locality in Ghaziabad.

Police identified the man as 30-year-old Monu Singh, a site engineer and supervisor, the first person to be arrested in the case late on Friday night.

"The man is a site engineer and supervisor and allegedly was not at the site when the five workers died inside a sewer manhole. He is resident of Sanjay Nagar," said Shlok Kumar, superintendent of police (city).

The Uttar Pradesh (UP) water utility Jal Nigam on Friday also suspended work on the new sewer line. The UP government had earlier blacklisted the firm contracted for the project.

"We have suspended work as of now as the government has blacklisted the contractor company which was taking up construction. It is still not clear whether the same company will finish the swer line laying project or we have to re-tender the work and engage some other company. We will seek directions from the state administration and take up the work accordingly," said GS Srivastava, chief engineer of the UP Jal Nigam.

The Uttar Pradesh government had also suspended four engineers of the UP Jal Nigam on Thursday.

According to officials, the sewer line project is
estimated to cost about ₹88.75 crore, which includes the construction of over 47 km of sewer line.

"The manhole where the five workers died was constructed one month ago. There is no sewer flow under the entire 47km of the new network. The work for connecting 29km lines is complete. The incident is tragic and no one expected that the unconnected sewer may have gaseous formation
which resulted in death of five workers at the site," the chief engineer added.

The Ghaziabad police had identified the five victims as Vijay Kumar, 40, his brother-in-law Shiv Kumar, 32, besides Horil, 35, Sanjeet, 30 and Damodar, 40.

They all suffocated to death, post mortem reports received by police on Friday said.

The officials of the UP Jal Nigam said that a team of engineers will also take up a detailed inquiry about the reasons, laxity and other issues that resulted in deaths of five workers.

"We have come to know that the contractor company is a joint venture company with two firms taking up the work. We have directed that officials of both the companies should be named in the FIR," said Manju Diler, member of the National Commission for Safai Karamcharis, who visited the site in Ghaziabad on Friday.