A man and his son were washed away by strong current of Bhogdoi river in Jorhat district when they were taking bath, officials said.
NDRF and SDRF personnel have launched a search operation to trace them but still there is no whereabouts of the father-son duo.
Meanwhile, Assam State Disaster Management Authority (ASDMA) said more than 1.05 lakh people are reeling under the flood in 138 villages across Lakhimpur, Golaghat, Morigaon, Barpeta and Jorhat districts.
Authorities are operating eight relief camps and distribution centres in two districts.
Nearly 7,000 hectares of crop have also been damaged in these districts.