Deajah Stevens, a Rio Olympic sprinter, and fellow Tokyo Olympic hopeful Gabby Thomas, have been provisionally suspended for drug - testing whereabouts failures.
Xinhua news agency quoted local media reports as confirming this on Friday.
A suspension for whereabouts failures means any combination of three missed drug tests and/or filing failures in a 12 - month period.
A filing failure could mean incorrectly filling out forms to tell drug testers where an athlete can be found, or not submitting regular forms at all.
According to a statement from the Athletics Integrity Unit, Stevens amassed three whereabouts violations in a year.
Stevens won the US national title in the women's 200 meters in 2017 and was a finalist in the 200m at the 2016 Rio de Janeiro Olympics.
Thomas won the second place at the 2018 NCAA Outdoor Championships women's 200m with Harvard.