The floods have hit 10 districts --Hojai, Karimganj, Morigaon, Nagaon, Dima-Hasao, Cachar, Dibrugarh, Hailakandi, Golaghat and Karbi Anglong West-- as the situation remains grim, Xinhua reported.
"In Assam, the flood situation remains grim as 625,318 people are reeling under the deluge across 10 districts," an official said. "Four people have lost their lives in the past 24 hours and the number of deaths caused by the floods has so far reached to 18."
Officials said at present 577 villages are inundated and about 6,023 hectares of crop area have been damaged across the affected districts.
According to the Assam State Disaster Management Authority (ASDMA), the local government has opened 191 relief camps and 108 distribution centers in the affected areas.
Authorities have also canceled some trains owing to the damage to railway tracks in the affected areas.
The flooding hit the twin states of Assam and Manipur following heavy rains in the aftermath of cyclone Remal, which made landfall between the coasts of West Bengal and Bangladesh last month.