A group of 18 state attorneys general have urged United States President Joe Biden to help free Binance executive Tigran Gambaryan from his Nigerian detention.

The attorney generals have asked President Biden to designate Tigran Gambaryan as a hostage under the Robert Levinson Hostage Recovery and Hostage-Taking Accountability Act.

The attorneys raised concerns over Gambaryan’s deteriorating health and unlawful detention in Nigeria, according to a joint letter issued on Oct. 18.

Attorney General John Formella wrote in the joint letter:

“His continued detention without cause is not only a violation of his rights but also poses a severe risk to his health and well-being… It is our duty to advocate for U.S. citizens abroad, and we urge the federal government to apply the necessary diplomatic pressure to secure his release.”

Tigran Gambaryan in court. Source: Nairametrics

Concerns increased over Gambaryan’s well-being on Oct. 18 after a judge postponed his hearing. The detained Binance executive was too ill to appear in court. His hearing was adjourned to Oct. 25.

This is a developing story, and further information will be added as it becomes available.

Related: Binance CEO calls Gambaryan’s treatment ‘inhuman’ as disturbing new video emerges