Ammonia gas leaked from a subsea pipeline linked to a fertiliser manufacturing unit situated on the shoreline in north Chennai, affecting people by causing shortness of breath, nausea and faintness and approximately 25 of them have been hospitalised, official sources said on Wednesday.

Following the leak, at about 11.45 pm on December 26, an odour that caused severe discomfort to people spread through air in north Chennai areas. A number of persons fainted after experiencing 'burning sensation' in their throat and chest. Many people who were asleep woke up in panic and scurried out of their homes and alerted neighbours and all of them soon reached the main roads unsure of what to do.

For the people of north Chennai, it was double whammy, as they were affected by the recent oil spill and now the ammonia gas leak. About 25 people including children, who were residents of areas close to the fertiliser manufacturing facility were hospitalised. Most of them experienced unease, shortness of breath, nausea, and faintness.

According to representatives of fishermen villages, Chinna Kuppam, Periya Kuppam, Netaji Nagar, Burma Nagar in north Chennai were among the affected neighbourhoods.

People had a tough time finding vehicles midnight and used whatever vehicles were available like autorickshaws and motorcycles to reach hospitals.

An elderly woman fainted after bouts of vomiting and she was rushed to a hospital in an autorickshaw. Buses and ambulances were also deployed by authorities to immediately bring affected people to hospitals many kilometers away from the location of the fertiliser unit.

Some fishermen and local people who happened to be on the beachfront at midnight noticed unusual sound and water gushing out from select spots above the subsea pipeline.

Health Minister Ma Subramanian visited the Government Stanley Medical College Hospital here and spoke to people admitted from gas-hit areas and interacted with hospital authorities.

Coromandel International Limited, a Murugappa group company said in a statement: "As part of routine operation, we noticed abnormality on 26/12/2023 at 23.30 hrs in the ammonia unloading subsea pipeline near shoreside, outside the plant premises. Our Standard Operating Procedure activated immediately, and we have isolated ammonia system facility and brought the situation to normalcy in the shortest time." During the process, the company said, "few members in the local community expressed discomfort and were given medical attention immediately. All are safe and normalcy is restored. We have informed relevant authorities about the incident. Coromandel has always adhered to the highest safety standards and emergency response system." After the company officials 'addressed' the issue, police personnel pacified people who gathered on roads and requested them to go back to their homes as 'there is no problem'.

Agitated residents, however, gathered in front of the fertiliser manufacturing company's premises this morning and raised slogans and demanded the unit's immediate closure.

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