The boat capsized in the swollen river, Sub-divisional Officer (SDO) Prabhat Bhushan said.
While three persons drowned in the river, six others went missing, he said, adding several others swam to safety.
The three bodies were fished out by local divers while a hnt is on to trace others.
The occupants of the boat were going to the other side of the riverine area to collect fodder for their cattle.