A Vietnamese fishing boat was crashed by an unidentified cargo ship off the coast of the central province of Quang Tri on Tuesday.
The boat was fishing on the waters, some 97 nautical miles southeast of Con Co Island, when the unknown ship crashed and submerged it.
Six crew members fell into the water; five of them were soon rescued by a nearby fishing boat.
The unknown ship quickly fled the accident scene.
The two fishing boats are still searching for the missing fisherman.