It was very difficult for drivers on drugs to come clean and if authorities do not keep them off the streets, they will continue causing more serious traffic accidents, Tien said at a traffic safety meeting on Monday.

Tien was agreeing with a proposal made by Nguyen Anh Cuong, vice chairman of the northern Hai Duong Province, where eight people on a highway were fatally mowed down by a truck whose driver took meth several days before in January.

Cuong had suggested that the Transport Ministry permanently revokes driving licenses of drivers found using drugs when violating traffic rules.

"The current regulation, which revokes the driving license for six months, is not strict enough to force addicted drivers to go to rehab clinics. Not only that, there have been cases in which drivers are unable to get clean and it is possible that they can still cause accidents once they get their licenses back," he said at the meeting in Hanoi that discussed measures to ensure traffic safety.

Transport Minister Nguyen Van The did not respond immediately to the suggestion but affirmed that his ministry was working on revising upward the fines and other punishments for those violating traffic rules.

The ministry will also install more CTTV camera along streets to keep a closer watch on violations, he said.

Prime Minister Nguyen Xuan Phuc also stressed for heavier punishment for drivers who are caught with  drugs or alcohol.

Phuc said driving licenses of those addicted to drugs and alcohol should be cancelled and those driving with 80 milligrams of alcohol in 100 millimeters of their blood should face criminal charges. The presence of alcohol in a driver’s blood or breath now attracts fines of VND2 to 18 million ($85-767).

Drug use is not rare among Vietnamese truck drivers with heavy workloads, surveys have found.

In a scattered 20-day inspection starting January this year, traffic police found 182 truck and minibus drivers high on narcotics. In the first half this year, they had handled 239 cases in which drivers were using drugs when driving, according to the National Traffic Safety Committee.

In January, besides the Hai Duong accident, four other people died and 16 were injured in the southern Long An Province after a truck slammed into motorbikes waiting at a traffic light. Tests found the 32-year-old truck driver was high on liquor and heroin.

Road crashes are a leading cause of deaths in Vietnam, killing almost one person every hour.

Almost 3,740 traffic accidents were killed in 8,280 cases of road accidents in the first half of this year killed, down 290 in number of death and 610 in number of cases compared to the same period last year.