A case was registered and investigation is on, police said.
Carcasses of 20 monkeys were found in a water tank in Nalgonda district of Telangana, police said on Wednesday.
The monkeys had fallen into the water tank located in Nandikonda Municipality of the district, while trying to drink water in it and drowned, they said.
The water tank is a old structure with tin roof which was slightly opened, they added.
People residing in the vicinity alerted the authorities after a foul smell emanated from the tank.
Later, municipality workers found the monkeys dead inside the tank and removed the carcasses.
A case was registered and investigation is on, police said.
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