Editor's Note: This article was upated at 4:20 EDT to include additional information.

A major Thoroughbred racing stable was the subject of a 2013 undercover investigation by People for the Ethical Treatment of Animals (PETA), which alleges over-medication of and cruelty to horses, as well as use of electrical devices on them. Racing regulators are investigating PETA's claims.

The New York Times published an article on the PETA probe in its March 20 edition and posted on its website late March 19. In the story, the Times said it reviewed all documents, about seven hours of video, and related complaints, but had no part in the investigation.

The newspaper said it wrote the story on the condition it not publish the name of the investigator, who is said to have worked for trainer Steve Asmussen and his assistant, Scott Blasi, for four months at Churchill Downs, in Louisville, Ky., and Saratoga Race Course, in Saratoga Springs, N.Y