Nigerian sprinter Nzubechi Grace Nwokocha, who won gold in the 4x100m relay at this year's Commonwealth Games, has been provisionally suspended for the use of banned substances, the Athletics Integrity Unit (AIU) said on Saturday.
Nwokocha, 21, ran the anchor leg in Birmingham last month as Nigeria beat England and Jamaica to take gold.
"The AIU has provisionally suspended Nigerian runner, Nzubechi Grace Nwokocha, for the Presence/Use of Prohibited Substances (Ostarine & Ligandrol) (Article 2.1 and Article 2.2)," the body said in a statement on Twitter.
Ostarine and Ligandrol are both anabolic agents prohibited by the World Anti-Doping Agency (WADA).
A provisional suspension means an athlete is temporarily banned from competition before a final decision is taken at a hearing conducted under WADA rules.
Nwokocha qualified for last year's Tokyo Olympics and also entered the 100m and 200m at the world championships in Eugene this year, reaching the semi-finals in both events.
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