LONDON: A leading trainer from the powerful Godolphin stable was charged yesterday in connection with one of the biggest doping scandals to hit British horse racing.

Mahmood Al Zarooni was charged with violating multiple rules related to banned substances in horses after samples from 11 of his horses at stables in Newmarket were found to contain traces of anabolic steroids.

The British Horseracing Authority also charged the 37-year-old trainer with failing to keep medication records and with conduct prejudicial to the sport.

Al Zarooni, one of two British-based trainers for Godolphin, was ordered to appear before a BHA disciplinary panel in London today and could be stripped of his license.

Godolphin is the racing organization of Dubai ruler Sheikh Mohammed bin Rashid Al Maktoum, who has owned a number of the world’s greatest horses since establishing his operation in 1992. The racing outfit said he was “appalled” by the doping case.

Al Zarooni said Monday he deeply regretted making a “catastrophic error,” saying the horses involved weren’t racing at the time so he “did not realize that what I was doing was in breach of the rules of racing.”

In a statement yesterday, the BHA said Al Zarooni has told investigating officers that he administered four more horses with prohibited substances ethylestranol and stanozolol — the same steroid found in the urine of Canadian sprinter Ben Johnson in his positive test at the 1988 Olympics in Seoul.

Those four horses weren’t tested when the BHA took samples on April 9 from 45 horses trained by Al Zarooni at Moulton Paddocks stables.

Al Zarooni has trained some high-profile winners, notably Monterosso in the 2012 Dubai World Cup — the world’s richest horse race, since being employed by Godolphin in 2010.

One of the horses that tested positive is Certify, an unbeaten 3-year-old filly who would have been a leading contender for the 1,000 Guineas at Newmarket on May 5. Certify has been pulled out of the race.

British bookmakers said they would refund bets that have been placed on horses trained by Al Zarooni.