Volkswagen dealers in Canada have been told to stop selling diesel-powered vehicles involved in an emissions-testing scandal.

The Canadian division of the German automaker is working with its American counterpart and parent company to resolve the issue.

The U.S. Environmental Protection Agency (EPA) says Volkswagen programmed the computers in the vehicles in question to recognize emissions testing and turn on extra pollution controls that are not otherwise engaged.

In other words, the tests were manipulated to fool American regulators.

The models Volkswagen has stopped selling in Canada include the 2009-2015 Golf, Jetta and Beetle cars and 2012-13 Passat which are equipped with the same diesel engines as the cars stateside.

The models have not been recalled.

About two in 10 vehicles Volkswagen sells in Canada have diesel engines.

Canadian regulators do not independently test vehicles to make sure they comply with requirements, but instead rely on EPA test results.

CEO Martin Winterkorn, says he is ”deeply sorry” that the automaker has broken the trust of customers and the public.

VW will co-operate with regulatory agencies and has ordered its own internal investigation.

Winterkorn adds, ”We do not and will not tolerate violations of any kind of our internal rules or of the law.”