According to officials, two weeks of heavy rains caused one of Asia's largest rivers to overflow.
The Brahmaputra River continued to wreak havoc, displacing more than 2 million people, the officials said.
Vast tracts were still underwater with 26 of the state’s 33 districts badly affected.
M.S. Mannivanan, head of the State Disaster Management Authority, said rescue and relief operations were underway.
“We have 40 teams of the State Disaster Response Force in the worst-hit areas and the army also is on standby,” Mannivanan said.
The Brahmaputra River, which flows through Tibet, India and Bangladesh, burst its banks in Assam late last month, inundating large swathes of the state and triggering mudslides.
“The situation is grim, although the Brahmaputra's waters have receded slightly today with the intensity of rains coming down a bit,” Manninanan said.
Thousands of people were taking shelter Tuesday on a raised river embankment after being displaced from their submerged homes in central Assam’s Morigaon district.
“Our villages and all nearby villages have been under chest-deep water for about a week now,” said Nilima Khatun, who was clutching her 2-year-old child. “We are passing days in misery with no relief coming our way from the government.”
The floods also inundated most of Kaziranga National Park, home to rare one-horned rhinos, authorities said.
In the Pabitora wildlife sanctuary, 35 kilometers (21 miles) east of the state capital, Gauhati, an entire one-horned rhino population of over a hundred were taking shelter in artificially built highlands.
“The entire park is submerged with the rhinos moving to the highlands for shelter," park ranger Mukul Tamuly said by phone.
Annual monsoon rains hit the region in June-September. The rains are crucial for rain-fed crops planted during the season but often cause extensive damage.
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