The incident took place at around 15.30 hrs at Solanpada Dam in Karjat in neighbouring Raigad district, about 100km from here, police said.
By the evening, the police had fished out two bodies with the help of local residents, while efforts were on to trace the third person accompanying them, they said.
One of the bodies was that of Pravin Tukaram Rane (24), a resident of Poshir village in Karjat taluka, while the second deceased was yet to be identified, a police official said.
An accidental death case has been registered at the Karjat Police Station, the official added.