A U.S. official says a Canadian doctor who has treated golfer Tiger Woods and many other pro athletes is under a joint U.S.-Canadian investigation for possibly providing performance-enhancing drugs.

The official familiar with the investigation says Canadian authorities have been investigating Dr. Anthony Galea, who was arrested Oct. 15 in Toronto, and the FBI has been brought into the case.

The official said Tuesday the investigation was being conducted by the Royal Canadian Mounted Police. The official was not authorized to discuss the case and therefore spoke on condition of anonymity.

The New York Times first reported on the investigation. Speaking to the newspaper, Galea denied wrongdoing.