The incident took place on the premises of Matsya Gireendra Swamy temple at Kothagattu village, about 30km from here, Huzurabad Deputy Superintendent of Police P Sanjeev Kumar said.
Before entering the temple, the four went to take a holy dip in the tank where they drowned, he said.
The deceased were identified as L Swapna, S Vahini and B Sridhar (all 21) and Gollapalli Kiran (22). Their bodies have been fished out, police said.