The victims aged 33 to 37 hail from Quang Ninh, Phu Tho, Thai Nguyen and Cao Bang provinces.
Hearing about the news, leaders of Quang Ninh fanned out to the scene to direct search and rescue work.
Around three hours after the accident, rescue workers retrieved the victims from the debris.
The local administration, trade union and relevant agencies provided financial assistance to the bereaved.
An investigation into the cause of the accident was launched by local officials.