The bodies have been recovered from the manhole and sent to a hospital for post-mortem. (File photo)
Three labourers were found dead after inhaling toxic fumes while cleaning a clogged manhole here, said a civic official on Tuesday.
"Though the incident occurred on late Monday night, the labourers' death came to light earlier in the day when passersby alerted the fire and emergency services brigade," Bruhat Bengaluru Mahanagara Palike (BBMP) Commissioner Vikas Gowda told reporters here.
The victims were identified as Erraiah, 35, Anjaneya Reddy, 34, and Thavatheen Naidu, 40, from the neighbouring Andhra Pradesh.
Police are on the lookout for the contractor of the state-run Bengaluru Water Supply and Sewerage Board (BWSSB), who hired the victims for cleaning the choked manhole of filth, which blocked the drainage pipes.
"When two of the victims, who entered the 15-metre manhole suffocated due to lack of oxygen and fell unconscious, the third victim jumped into the pit to rescue them but he too succumbed to the toxic fumes," said Mr Gowda.
Bengaluru Development Minister KJ George, who rushed to the spot for firsthand information about the tragic incident, announced Rs 10-lakh compensation to each of the victims' kin and ordered an inquiry.
"It is an unfortunate incident. The contractor should not have used manual labour to clean the manhole but a jetting machine. I have told the BWSSB to probe the mishap and take stringent action against the contractor," the state development minister told reporters.
The civic agency personnel retrieved the bodies from the manhole and sent them to a government hospital for post-mortem.
Hyderabad-based Ramkey Enterprises, which bagged the contract to clean some of the manholes in the city, sub-contracted the work to a local contractor.