Heavy rains and overflowing rivers have swamped 23 districts in northern and north-west Bangladesh, according to officials
At least 30 people have been killed since the floods began last week.
Rain-swollen rivers in Bangladesh broke through at least four embankments, submerging dozens of villages and doubling the number of people fleeing their homes overnight to 400,000 in one of the worst floods in recent years, officials said on Friday.
Aside from concern over crops, authorities are also worried that rising floodwaters could take a toll on livestock.
“The severity of the flood of this year is worse compared to recent years,” Ariful Islam, an executive engineer of Bangladesh Water Development Board, said.
South Asia receives monsoon rains between June and October that often lead to floods later in the season, but the intensity of the deluge in Bangladesh is uncommon.