Three Republic of Korea (RoK) people were killed in a car crash early on the expressway en route to the northern province of Thai Nguyen.
The victims were travelling on a Toyota 7-seater van with the license plate of BKS 99A-080.65 when it hit into the back of a truck moving on the same direction.
The accident reportedly occurred at 2:30am on the Hanoi-Thai Nguyen expressway, said the Thai Nguyen city police.
The strong crash flew the van over to the road fence, with the first half part completely smashed into pieces.
Both the van driver and two passengers were killed at the scene.
The truck was thrown away lying on its side a few metres from the van after the crash. Its driver, Bui Van Minh, 30, had slight injury on his arms.
An official of the Thai Nguyen Department of Transport later told reporters that the three victims were identified as Yu Gyeong-hyeon, 25; Yu Jong-heon, 28; and Choi Hong-seong, 38.
The cause of the accident is under investigation.
Right after hearing the case, Deputy Prime Minister Nguyen Xuan Phuc, Chairman of the National Committee for Traffic Safety sent his deep condolences to the families of the victims and instructed authorised agencies to promptly address the consequences of the accident.