The British Horseracing Authority (BHA) has confirmed that Newmarket-based trainer Gerard Butler is under investigation following positive tests for a banned substance in February. Butler told the Independent that, in what he described as an “unpardonable misjudgement”, four of his horses had been treated with Sungate, a joint treatment which contains a banned substance, on the advice of his vet. His admission comes hot on the heels of the BHA’s decision to ban trainer Mahmood Al Zarooni for eight years after he admitted to using anabolic steroids on some of his horses.

A BHA statement read: “It is the general policy of the BHA not to comment publicly regarding ongoing investigations or speculation surrounding potential investigations. However, in light of reports and speculation, and because of recent events regarding horses formerly trained by Mahmood Al Zarooni, it is felt necessary to confirm that a separate investigation is being held into a number of positive samples obtained from horses at Gerard Butler’s yard, following a testing in training visit on February 20.

“While conscious of the need not to prejudice the outcome of the current inquiry, the investigation has established that the source of the positive samples was a veterinary product, licensed in the EU and legally imported for use by a veterinary practice, the initial administration of which was recommended by a vet. This investigation remains ongoing and a number other parties have been and will be interviewed, including representatives of the veterinary practice in question.”

“Immediately following the results of the testing in training, the BHA, in conjunction with the National Trainers Federation, notified trainers that the product in question contains an anabolic steroid and should not be used on any horse in training.”

The NTF, which represents the interests of British handlers, confirmed it had told its members of the issue last month.

A statement from the organisation read: “In responding to a report in the Independent newspaper about positive samples taken by the BHA from horses trained by Gerard Butler in Newmarket, the National Trainers Federation is mindful that the investigation is continuing. Therefore, other than to confirm that at the BHA’s request, we notified our members in March this year to avoid using a specific veterinary product because it contains an anabolic steroid, we will not be saying more at this time.”

The BHA confirmed some of Butler’s horses returned positive results after random tests in February and it is trying to establish how many horses have been affected, with Butler suggesting other yards in Newmarket may have used the product.

Butler described Sungate as “misunderstood by many others” and underlined the fact the BHA had not commented on its inclusion in the yard’s medical book.

Butler told the Independent: “I have been totally candid throughout, and it was I who told the BHA that I had treated four colts in December and January. And I must emphasise I was advised in good faith by my vets. It was an unpardonable misjudgement, purely to cut corners in what is a very expensive treatment. I have been very uncomfortable over the past few days, hearing and reading about the Al Zarooni case. I feel people need to know about what has happened in my yard.”