The Treasury Department on Tuesday announced new sanctions targeting firms involved in the production or transfer of Iranian drones to Russia for use in attacks against civilian infrastructure in Ukraine.

The department’s Office of Foreign Assets Control (OFAC) designated Shahed Aviation Industries Research Center, which it accused of manufacturing the drones, including the single-use Shahed-136 drones that struck civilian targets in Kyiv and other Ukrainian cities in mid-October.

Also designated were two United Arab Emirates-based air transportation firms accused of facilitating the drone shipment. OFAC described one of the firms, i Jet Global DMCC, as having allegedly used its Syria branch to assist US-sanctioned Syrian airline Cham Wings in facilitating the transport of Syrian fighters to Russia.

Some nine months into its war in Ukraine, Russia has turned to cheap Iranian-manufactured drones as its own arsenal of advanced weaponry has dwindled. In September, the Treasury Department sanctioned an Iranian air transportation service provider and three companies for their alleged involvement in the drones’ production and shipment to Russia.