The water level in the Brahmaputra, Teesta, Dharla and Dudhkumar rivers swelled further today due to onrush of water from hills and incessant rainfall for the last few days.
Locals said low-lying areas in 25 unions under Sadar, Bhurungamari and Nageshwari upazilas were flooded, leaving 50,000 people marooned.
Officials at Bangladesh Water Development Board said the Dharla River was flowing 28 cm above its danger level. Besides, the water level in the Brahmaputra went up by 35 cm, while in Dudhkumar by 32 cm and in Teesta 25 cm during the last 24 hours.
Meanwhile, 10 villages in Sadar upazila went under water after a dam in Halokhana Sarodoba area collapsed.