The fish were found dead in the lake - spread over a five acre area - on Sunday. The fact that the drainage discharge from a broken drainage line of the PCMC has caused the pollution of the lake came to light on Monday.

PCMC garden superintendent Suresh Salunkhe confirmed that water from the broken drainage line entered the lake due to which oxygen level of the water dipped, killing thousands of fish. "I think all the fish in the lake have died," he said. Salunkhe said an auditorium being built by the PCMC is coming in the vicinity of the lake. "While the work on the auditorium was going on, the drainage pipeline broke resulting in the discharge of drainage water into the lake," he said.

The lake, constructed by the PCMC in 1997, and the boating facility are looked after by a private contractor. The garden is maintained by another private party.