The state-owned Iran newspaper said the toll was likely to rise as six vehicles including a bus were buried in the mud with no news of the fate of passengers trapped inside.
More than 210 villages in the province of Golestan were affected in the same places where some 300 people were killed last year in the worst floods in the area for two centuries.
The main road from the capital Tehran to Mashhad, the biggest city in the northeast, remained under water on Wednesday hampering rescue efforts in the region.
Heavy winter rains this year ended three-year drought which has affected much of Iran and neighbouring Afghanistan.
- Reuters - Thomson Reuters Foundation
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