Last updated on .From the section Northern Ireland

The Irish Greyhound Derby takes place at Shelbourne Park on 23 September

The winner of one of Ireland's top greyhound races has tested positive for cocaine.

Clonbrien Hero was found to have traces of the prohibited substance benzoylecgonine - external-link the main compound of cocaine - in its urine on three separate occasions.

One of the tests was after the dog won July's Irish Laurels final at Cork.

The Irish Greyhound Board has withheld prize money and banned the dog from racing until it has been passed clear.

In a statement referencing a previous case external-link earlier this year, the IRB said they drug test between 5,000 and 6,000 greyhounds per year - the "most intensive testing regime of any sport in Ireland".

Clonbrien Hero's trainer Graham Holland said the traces of the drug must have been ingested accidentally external-link .

Holland was in the headlines last year when the greyhound Clares Rocket was abducted from his kennels in Tipperary. The dog was later recovered unharmed.