A section of the Giaspura locality in Punjab’s Ludhiana underwent a night-long decontamination process after 11 people died from allegedly inhaling toxic gas and the area remained cordoned off on Monday, the district authorities said.

Teams of the Punjab Pollution Control Board (PCB) checked what led to the build-up of Hydrogen sulphide in the sewer that might have led to the tragedy, the officials said, adding that the poisonous gas is no longer being detected in the air. A magisterial inquiry has already been ordered into the incident.