The crash occurred at about 10.10 pm at kilometre 33+500 on National Highway 4B, in hamlet 8+10, Na Duong Commune, Lang Son Province.
According to initial reports, one motorbike was travelling from Loc Binh towards Loi Bac when it collided head-on with another bike travelling in the opposite direction.
The four victims, all residents of Loi Bac Commune, included three teenage boys aged 15, 17 and 18, and a 20-year-old man.
All four died at the scene following the impact.
The scene of the accident (Photo: Lang Son Television).
Lang Son Provincial Police Department dispatched officers from Na Duong Commune police and other units to provide emergency assistance, secure the site and regulate traffic.
Authorities are investigating the cause of the crash.
