Two people on the bulkhead went missing after the incident. They are Milon and Kalam Sizuddin of Nanduhar village under Swarupkathi upazila of Pirojpur.
The launch has also been affected by the incident.
Later, the launch is anchored in the Chowdhuryhat area and all passengers are safe.
Ujirpur Police Station Officer-in-Charge Ali Arshad said they are on the spot.
"Efforts are on to find out the missing two people," he added.