Rep. James Comer (R-KY) issued a subpoena to FBI Director Christopher Wray on Wednesday, ordering him to hand over a bureau form that allegedly describes a “criminal scheme” involving then-Vice President Joe Biden and an unnamed “foreign national.”

Comer, the chairman of the House Oversight Committee, described the reasoning behind the subpoena in a letter sent to Wray and Attorney General Merrick Garland. The letter was authored jointly with Sen. Chuck Grassley (R-IA). Comer and Grassley, who are both leading investigations into Hunter Biden and the Biden family generally, did not provide many specifics on the wrongdoing being alleged.

“We have received legally protected and highly credible unclassified whistleblower disclosures,” the congressman and senator told Wray and Garland. “Based on those disclosures, it has come to our attention that the Department of Justice and the Federal Bureau of Investigation possess an unclassified FD-1023 form that describes an alleged criminal scheme involving then-Vice President Biden and a foreign national relating to the exchange of money for policy decisions. It has been alleged that the document includes a precise description of how the alleged criminal scheme was employed as well as its purpose.”