The US Department of State says it is aware of the reports of the detention of its citizen in Abuja, Nigeria’s capital.
Binance executive Tigran Gambaryan was arrested last month – together with his colleague, Nadeem Anjarwalla, who holds both British and Kenyan passports – as part of a tax evasion probe against the cryptocurrency platform.
“When a US citizen is detained overseas, the department works to provide all appropriate assistance,” a spokesperson for the American Embassy in Nigeria told the BBC.
The embassy declined to provide further comments on the detention citing “privacy considerations”.
Although Mr Anjarwalla is no longer in Nigerian custody following confirmation by authorities of his escape with a “smuggled passport”, a close family source said he left Nigeria through “lawful” means.
Nigerian authorities say they are working with Interpol to issue an international warrant for his arrest.
Authorities on Monday formally filed tax evasion charges against Binance at the High Court in Abuja, and named Mr Anjarwalla among the respondents.
The Federal Inland Revenue Service is accusing the cryptocurrency platform of non-payment of value added tax, company income tax, failure to file tax returns and complicity in aiding customers to evade taxes through its platform.