South Korea’s Environment Ministry filed a criminal suit with the prosecution Tuesday against the local unit of Volkswagen over the global automaker’s emissions rigging scandal.

The suit was filed against Johannes Thammer, managing director of Audi Volkswagen Korea, after the world’s largest automaker failed to satisfy the nation's legal requirements in its recall plan, the ministry said.

Thammer was accused of violating the Clean Air Conservation Act, which can carry a prison term of up to five years and a penalty of up to 30 million won ($25,000).

The decision came after the ministry determined that the recall plan submitted by VW Korea was missing such key elements as the cause of defects and the plan to improve them as required by law. 

The company was ordered to submit a detailed recall plan including how to improve emissions results and maintain fuel efficiency after removing the emissions-cheating software by Jan. 6. 

After conducting its own emissions tests for two months, the ministry found that VW models had used “defeat-device” software to bypass emissions tests. It ordered the carmaker to recall about 125,000 vehicles and fined it 14.1 billion won ($11.6 million) in November. 

A spokesperson from the company did not offer its official stance on the suit, saying that it had only learned about the ministry’s plan to file a complaint through local media in the morning.

It is the first time for the government to file a suit against the German company, though a local civic group sued Thammer and Thomas Kuehl, the VW Korea chief, on the same charges last November.

Earlier in the day, six key Volkswagen company officials including Thammer and Friedrich Eichler, VW’s powertrain development chief, visited the ministry to offer an explanation about the technical solutions to the defects.

"Audi Volkswagen Korea is putting utmost efforts to resolve the emissions issue," the company said in a statement. "The executives from the German headquarters visited the Environment Ministry to implement the recall plan rapidly and systematically in the Korean market.” 

Regarding the visit, the ministry said it was irrelevant with the criminal suit and that it was to exchange opinions on how to carry out the recall plan.

The ministry is considering filing an additional complaint against the company on charges of discharging excessive level of hazardous gases into the air and using unauthorized car parts after consulting legal experts here.

The Transportation Ministry, meanwhile, said it plans to launch fuel efficiency tests on VW vehicles involved in the emissions-cheating scandal next week.

Last week, the California Air Resources Board also disapproved VW’s recall plan for the U.S. market, citing insufficient information on fuel efficiency, emissions and safety.

By Ock Hyun-ju (laeticia.ock@heraldcorp.com)