In Hanoi and HCMC, motorbikes account for 94 percent of hydrocarbon and 87 pct of carbon monoxide emissions.
'All local artists are outraged by the paintings which are bad and superficial copies. Anyone can see they are fake.'
Dual nationality is not allowed for Vietnamese citizens.
The act was caught on camera, prompting an investigation.
The country's tourism growth was behind many other countries in Southeast Asia.
The TripIndex 2016 ranks the city above Mumbai and Bangkok in terms of affordability.