Officials in Bangladesh say at least 27 people died when a small ferry packed with more than 100 people sank following a collision with a cargo vessel.
Police say it is unclear how many passengers are still missing after Thursday's incident on the Kirtonkhola river near Barisal.
They also had to suspend rescue operations after darkness fell.Witnesses say some passengers were able to swim to shore.
Boat travel is common in the delta nation, and fatal ferry accidents are frequent. A passenger boat sank earlier this month after colliding with a smaller ferry, killing 10 people.