Up to 30 percent of Ho Chi Minh City busses failed the city's first fleet-wide emissions test, an official said Thursday.
Le Hong Viet, deputy chief inspector at the HCMC Transport Department, said public and private busses that failed the initial test will be checked again in the next three months.
Penalties will be imposed if busses do not pass the second time around, he said.
The tests were inspired by the city's increasing pollution problem. According to a report released by the HCMC Environmental Protection Agency late last year, air pollution due to organic gasses shot up by as much as 220 percent since 2008.
The government issued a decree in June, ordering concerned agencies to tighten control over vehicle emission in the country, especially in big cities.
Under the decree, motorbikes will be required to undergo similar testing by 2015.