CHENNAI: Two persons died of asphyxiation when they opened the lid of a sewage chamber to remove silt deposits at Ordnance Clothing Factory (OCF) quarters, at Giri Nagar in Avadi on Thursday.

Police identified the victims as Moses (55) of Avadi and C Devan (50) of Pattabiram.

Following complaints from the residents of OCF, a private contractor was engaged to remove the blockage.

According to police, Moses opened the manhole lid of the chamber which connects the sewage line.

As soon as he opened the lid, the obnoxious gas hit Moses and he fell inside.

Devan who attempted to get hold of Moses also was hit by the gas and he too fell inside the pit, which is 3 feet wide and 15 feet deep.

A security guard of the apartment who ran to hold on to Devan was hit by the gas and fell unconscious on the ground.

The residents of OCF informed the police and fire service personnel. The fire service personnel reached the spot and fished out the two.

The ambulance crew reached the spot and declared the two dead. The security guard survived and he was rushed to the Avadi Government Hospital for treatment.

The Avadi Tank Factory police registered a case and sent the bodies for post-mortem to the Kilpauk Medical College and hospital.

Avadi Tank Factory Police registered a case against the person who engaged them for the work under IPC section 304-A (Causing death due to negligence).