The accident happened at 3.30am of April 14, around 130km from the shore of Thanh Hoa province, central Vietnam.
The Quang Anh 54 vessel was carrying 900 tons of cement from the northern port city of Hai Phong to Ky Ha when it collided with the Duy Phuong 36 ship, which was transporting 2,400 tons or rice from An Giang province in the Mekong Delta to Hai Phong.
After the crash, Duy Phuong was sunk while the cement ship had a hole on its stern.
The twelve sailors on Duy Phuong ship was taken to Quang Anh ship. The cement ship arrived at the Nghi Son Port in Thanh Hoa on the afternoon of the same day.
Investigators are inspecting the accident.