About 20,000 people have been affected by the flood water and many livestock washed away.
Road connectivity to the remote Bhergaon sub-division of the district has been snapped.
Affected people have taken shelter in schools and in high places.
The district administration is keeping a round the clock vigil on the situation.
Assam: Over 30 villages in Udalguri district have been inundated by flash floods following torrential rain since the last two days, official sources said on Monday.
First Published: Monday, June 04, 2012, 18:55