Police arrested two sub-assistant engineers attached to the Diamond Harbour municipality’s water supply department on Thursday night for their alleged negligence in ensuring the supply of safe drinking water in all 16 wards of the town.

The contractor assigned the task of maintaining the water processing and supply unit in the town has also been arrested for alleged negligence, because of which the residents of the town had to drink polluted water for a long time.

The two accused officers — Prabir Polley and Mridul Mondal (both SAE) — contractor Rahul Sheikh were produced in the additional chief judicial magistrate’s court in Diamond Harbour on Friday morning. Judge Payel Banerjee remanded the trio in jail custody for four days.

The trio were booked under several sections of the Indian Penal Code, including those for endangering the life and safety of others, adulteration and administering content with the intent to spread disease.

Insiders in the South 24-Parganas district administration as well as in the Trinamul Congress said the trio were arrested after a video of earthworm-infested water went viral and local MP Abhishek Banerjee sent across necessary instructions.

The visual of worms emerging from pipes supplying water in the 16 wards in the town caused discomfiture to the ruling party that runs the civic body and the administration was left with no option but to take the prompt action.

Embarrassment for the administration multiplied after some residents lodged complaints with the civic authorities about the supply of contaminated water.

“Quality of the municipality water was never good. But in the past one month, the quality deteriorated. Now earthworms are a regular feature of potable water here. The matter was brought to the notice of the municipality chairman but nothing was done,” a resident said.

Sources said after knowing about the lackadaisical approach of the civic authorities, the Diamond Harbour MP told police to begin a suo moto case against the engineers and the contractor entrusted with the supply of drinking water. On Thursday evening, a police team led by Diamond Harbour subdivisional police officer Mitun De visited the civic office and arrested the trio in the presence of a deputy magistrate.

De told The Telegraph: “The arrested persons cannot ignore their responsibility. They were arrested for negligence.”

Refusing to respond to the arrest, civic body chief Pranab Das said: “There are multiple problems in the water supply plant. We have been trying our best to ensure the supply of good water but pipes often get damaged and cause contamination.”

Polley’s lawyer Sudip Chakraborty said: “My client is a civil engineer and has been made a scapegoat. He knows nothing about water quality. The civic authority is responsible for the poor quality of water as they do not repair damaged lines.”