Former United States Attorney Preet Bharara is facing investigation by Turkish prosecutors for his role in putting a businessman on trial in New York on “politically motivated” charges, the country’s Anadolu Agency reported on Saturday.

The case in New York involves a banker, Mehmet Hakan Atilla, who was arrested in March for allegedly conspiring with others, including gold trader Reza Zarrab, to violate US sanctions against Iran. Atilla was the deputy general manager of one of the largest state-owned banks of Turkey, Halkbank.

The documents being used as evidence against Atilla have unknown and unofficial sources and violate international and domestic laws, the Istanbul prosecutor’s office said. An affidavit filed by Atilla’s lawyer claims that the documents “are stolen, fraudulent and unqualified in nature”.

Turkish officials have accused Bharara of having links with a Pennsylvania-based Muslim cleric, Fethullah Gulen, who Turkey blames for a failed military coup in 2016. The investigation also involves Bharara’s successor Acting US Attorney Joon H Kim.