Four other workers who peeped into the tank through the lid swooned and have been hospitalised, police said.
The victims were engaged in the unloading of crude palm oil, imported from Indonesia, from the ship to the tank when suddenly the flow of the oil reduced considerably following which one of the workers entered the tank to find out the reason.
As he did not return, two other workers also went in but they also failed to come up. When the other four workers looked into the tank through the lid, they found the bodies of the three the workers floating in the crude oil before they also swooned.
Other workers from the ship rushed and rescued them. The four were admitted to the Government Hospital here.
Fire and rescue service personnel retrieved the bodies of the three workers.
Though police said the cause of the mishap would be known only after investigation, some workers in the port said a generator was running in the barge and smoke from it might have entered the tank and turned toxic.
