Environmentalist SM Ghosh called the lake water toxic after the dead fish were found. (Representational)
A large number of dead fish have been seen floating in the water of south Kolkata's Rabindra Sarobar since Sunday, triggering fear about contamination in the water among environmentalists.
The state agency Kolkata Metropolitan Development Authority (KMDA), the custodian of the lake, confirmed the developments and said a team has been sent to the spot.
Environmentalist SM Ghosh said "dead fish is everywhere in the lake. Found yesterday and today. Lake water is toxic now."
Mr Ghosh said the dissolved oxygen level in the lake water appeared to be very very poor, causing the deaths of at least 25-30 dead fishes.
KMDA Chief Executive Officer Antara Acharya told PTI, "we have sent a team of experts after coming to know about the development."
To a question, Ms Acharya said there have been indeed instances of dead fish floating in the lake water for past two days and the KMDA will take remedial steps to increase oxygen level in the water, including putting in more algae and other watery plants.
Ms Acharya said "floating dead fish can be spotted in a waterbody for various factors. We have to find out what happened in Rabindra Sarobar."