Tigran Gambaryan, a compliance official from the prominent cryptocurrency platform Binance in the United States, embarked on a two-day business trip to Nigeria in February and has not yet returned.

On his journey to Nigeria in late February, Tigran Gambaryan, a key compliance officer at Binance, carefully packed a small suitcase with essentials for a brief stay.

Having previously worked in U.S. law enforcement, Mr. Gambaryan was well aware of the potential risks involved in this trip. Sources familiar with a prior visit recounted how he and his colleagues hastily departed Nigeria due to concerns about possible detention by local authorities. Despite the uncertainties, he reassured his wife that he would swiftly conclude his business and return home.

Presently, Mr. Gambaryan finds himself detained at Kuje prison in Abuja, Nigeria, a facility known for housing individuals associated with extremist groups like Islamic State militants and Boko Haram.

Following a meeting with government representatives in Abuja on February 26, Mr. Gambaryan, aged 39, along with a Binance coworker, Nadeem Anjarwalla, were unexpectedly taken to a guesthouse under the supervision of Nigerian security personnel. They remained confined there for close to a month without any formal charges being brought against them.

Subsequently, in late March, Mr. Anjarwalla, who serves as the company’s regional manager for Africa, managed to escape under mysterious circumstances. Reports initially indicated that he fled Nigeria after being granted permission by guards to attend Ramadan prayers.

Shortly after the escape, the Nigerian authorities leveled accusations of tax evasion and money laundering against Mr. Gambaryan, Mr. Anjarwalla, and Binance itself, implicating the company and two of its employees in similar criminal activities.