The vehicle coming from Patharkandi met with the accident at around 5 AM, Additional SP Remsanga said.
"Eight people, all of them from Patharkandi in neighbouring Karimganj district of Assam, were in the vehicle," Remsanga said.
While five passengers managed to come out, three persons were stuck inside the vehicle, he said.
Rescue workers were finding it difficult to take out those trapped in the vehicle as the river is flooded due to heavy rains.