In the first incident, two youth, aged 20 years drowned in Bhavani river in Mettupalayam, where they had gone to take bath, police said.
The bodies have been identified as that of Muthusha and Abhishek.
In another incident in Udumalpet in Tirupur district, Ganeshan (21) and Karthkumar (28) drowned in Amaravathi dam, when they were taking 'holy water' coming down from a temple there.
Both were the natives of a village in Dharapuram in Tirupur district.