RALEIGH, NC -- North Carolina has joined other states to launch an investigation into Volkswagen for altering software to produce false results on vehicle emissions tests, Attorney General Roy Cooper said Thursday.

Cooper and Attorneys General from at least 28 other states across the country will work together to investigate allegations that Volkswagen equipped 11 million diesel vehicles with software that could be used to cheat on emissions tests, potentially deceiving consumers and violating clean air standards.

“Misleading car owners and cheating clean air rules are serious allegations, and my office is investigating to ensure fair treatment for affected North Carolina consumers,” Cooper said.

A list of affected Volkswagen and Audi models and model years and instructions for vehicle owners is available at the U.S. Environmental Protection Agency’s recall website.

North Carolina consumers who own one of the affected diesel cars are welcome to file a complaint with Cooper’s Consumer Protection Division online at ncdoj.gov or call 1-877-5-NO-SCAM toll-free within the state.

States currently participating in the multistate investigation include: Alabama, Arizona, Arkansas, California, Connecticut, Delaware, Florida, Illinois, Indiana, Iowa, Kentucky, Maine, Maryland, Michigan, Mississippi, Nebraska, Nevada, New Mexico, New York, Oregon, Pennsylvania, Rhode Island, Tennessee, Texas, Vermont, Virginia, Washington, and Washington, D.C.