The body was found on the banks of Pimpalgaon village yesterday, API D M Thakur of Murbad police station said.
The deceased has not been identified yet and a man hunt has been launched for the accused, he said.
The victim was tied to a stone weighing around 20-25 kg, police said.
The body has been sent for post mortem and a case has been registered under the IPC against the unknown assailants.
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