The Mumbai Port Trust (MbPT) workers, most of whom reside at the nearby Haji Bunder, were the first to feel the effects of the chlorine leak. Minutes after the gas leak in the early on Wednesday, thousands of residents began to complain of burning eyes and chest congestion.

Of the 120 victims who were hospitalised, 62 were MbPT workers.

"The incident occurred around 3 am when most people were asleep. This added to the confusion as misinformation began to pour in,'' said Rajesh Shinde, who runs a small shop in the area.

Several port workers earn their livelihood by collecting coal that falls off during loading and unloading of ships. These men were the first to bear the brunt of the gas leak. The fumes later spread to the residential areas near Haji Bunder. "Most of those who were hospitalised were discharged by afternoon,'' said Sudhir Kamble, a worker.

Residents had seen the gas cylinders lying unattended for years. Mohammed Shaikh, a taxi driver, said that the dock near Haji Bunder was used several years ago for unloading of chemicals, but later only ships transporting coal started using it.

Though this small group of houses and hutments lies in central Mumbai, it is virtually cut off from the city because of poor roads and surrounding MbPT warehouses. The seclusion was obvious on Wednesday when panic spread that a poisonous gas leak had left scores ill and maybe a few dead in the area. By afternoon, however, the situation was normal and the only visible signs of the chlorine leak were a posse of policemen.