"The flood situation has worsened overnight, drowning two more people in parts of western Assam and displacing about 250,000," Bhumidhar Barman, Assam's revenue, relief and rehabilitation minister, told IANS.

Earlier, nine people were killed in a landslide in the adjoining state of Meghalaya late on Friday while four were drowned in Assam.

"The current wave of floods that began last week has hit about 1.1 million people in 13 of Assam's 27 districts and affected a crop area of an estimated 26,000 hectares," the minister said.

Indian soldiers on Sunday began a massive rescue and relief operation in parts of western and northern Assam with the rain-swollen Brahmaputra river cutting a treacherous swath across the region.

"Soldiers are engaged in rescuing marooned villagers in boats and rafts," Barman said.

A Central Water Commission bulletin on Sunday said all major rivers and their tributaries in Assam are flowing above the danger mark and in full spate. The worst hit by floods is the eastern district of Dhemaji where the authorities evacuated nearly 100,000 in the last two days.

"We have about 200,000 people taking shelter in makeshift arrangements on raised embankments, government schools and offices," said Diwakar Mishra, the Dhemaji district magistrate.