LANSING, Mich. — At least 27 state attorneys general are opening a multi-state investigation into Volkswagen after it came clean about rigging diesel emissions technology to pass U.S. smog tests.

Michigan Attorney General Bill Schuette’s office said Thursday he and at least 26 other attorneys general will send subpoenas to the German automaker. Spokeswoman Andrea Bitely says many states will investigate both through their consumer protection and environmental protection divisions.

Volkswagen is reeling from revelations it used secret software to thwart diesel smog tests on nearly a half million vehicles in the U.S.

Participating states include Alabama, Arizona, California, Connecticut, Delaware, Florida, Illinois, Indiana, Iowa, Kentucky, Maine, Maryland, Michigan, Mississippi, Nebraska, Nevada, New Mexico, New York, North Carolina, Oklahoma, Oregon, Pennsylvania, Rhode Island, Tennessee, Texas, Vermont and Virginia. Washington, D.C., also is involved.