The U.S. said it would pay up to $15 million for tips on Hossein Hatefi Ardakani, an Iranian businessman who is alleged to have helped acquire technology for attack drones sold to Russia.

The move to put out a bounty for information on an alleged export-control violation comes after the U.S. sanctioned and charged Ardakani, chair of an electronics company, over his alleged work sourcing dual-use technology for drone production by Iran’s Islamic Revolutionary Guard Corps.

The Commerce Department, which administers U.S. export controls, publicized the bounty on Wednesday.

The U.S. says Iran has supplied several varieties of drone that Russia has used in its war against Ukraine. That conflict, along with fears of China’s military ambitions, has been met with a dramatic expansion of the nation’s export-control regime.