Eight vessels were seized for violating laws
The incident occurred early Sunday.
Gazaria Naval Police In-Charge Abdur Razzak said: "Two of the missing workers are Aslam, 26, and Emdad, 40. The identity of the third worker is yet to be known."
Gazaria Coast Guard Petty Officer Abdus Samad said: "Eight vessels were seized and anchored in Gazaria ghat on Saturday night for violating laws.
"A Dhaka-bound passenger launch hit the vessel, due to poor visibility caused by dense fog. Four workers fell into the water; one managed to swim back and the others went missing."
The petty officer said: "The launch headed towards Dhaka's Sadarghat, where the coast guard arrested the owner and the master of the launch.
"The rescue operation is on."