Wichien Udomsak, mayor of Muang Amnat Charoen district in Amnat Charoen province, said an outer ring road of the district was flooded and traffic faced difficulties on Thursday. About 50 houses and paddy fields were also flooded.
He said construction work that blocked natural waterways was also to blamed for the flood.
Chatchai Phromlert, director-general of the Department of Disaster Prevention and Mitigation, said that floods hit five districts and one municipality in Prachin Buri, Si Sa Ket, Ubon Ratchathani, Chanthaburi and Trat.
They included Non Khun and Benchalak districts of Si Sa Ket and Det Udom district of Ubon Ratchathani.
He expected the situation would return to normal in most of the affected areas in a few days.