The Irish middleweight tested positive for a banned substance last Thursday
Michael O'Reilly admits he unintentionally took a supplement which may have contained a banned substance, according to reports this evening.
The Irish middleweight was provisionally suspended for a doping violation last week.
In a statement this evening, reported by RTE, the 23-year-old says was given the supplement "by someone unrelated to his team or association".
O'Reilly was tested before leaving for Brazil and was made aware on August 4 that there were adverse findings.
In the statement O'Reilly apologized to his fellow boxers, team mates, the IABA, Sport Ireland, the Olympic Council of Ireland and those who had supported him.