A Louisiana veterinarian has been charged with engaging in a scheme to influence the outcome of horse races by illegally treating horses with a synthetic drug.

The federal indictment accuses the veterinarian, Kyle James Hebert, of providing trainers with mislabeled syringes of dermorphin to inject in at least four horses that competed at Louisiana racetracks. Hebert's company operated veterinary clinics in Lake Charles and Sunset.

The indictment returned Thursday says Hebert told trainers that the drug would make the horses "focus" and run faster.

The U.S. Food and Drug Administration hasn't approved any drug containing dermorphin, which is naturally secreted by tree frogs.

The indictment charges him and a Nebraska-based company, Kohll's Pharmacy & Healthcare Inc., with conspiracy.

Hebert and the company didn't immediately respond to requests for comment.

[Editor's Note: Hebert has been in federal investigators' sights since at least late 2012, following the Louisiana State Racing Commission's suspensions of three thoroughbred trainers tied to the veterinarian. Read more about that here.]