The United States Treasury Department’s Office of Foreign Assets Control (OFAC) announced on Thursday that it had sanctioned several Iranian and Turkish companies and 31 aircraft associated with four Iranian airlines.

The companies were connected to Mahan Air, Meraj Air, Caspian Airlines, and Pouya Air. Two of the airlines had allegedly ferried weapons, fighters, and money to Iran’s proxies in Syria and Lebanon.

The Treasury Department noted in its statement that it has also “sanctioned nine individuals and entities procuring export-controlled, U.S.-origin goods for sanctioned Iranian airlines.”

Treasury Secretary Steven T. Mnuchin said that, in procuring parts and providing services for the fleets of sanctioned Iranian airlines listed, these companies “extend a lifeline to the IRGC-QF and enable the Iranian regime to transport weapons, fighters, and money to its proxies, including Hizballah, and to prop up the brutal Assad regime.”

Mnuchin added, “The deceptive practices these airlines employ to illegally obtain services and U.S. goods is yet another example of the duplicitous ways in which the Iranian regime has operated.”

The Iran-based Blue Airways and Turkey-based Otik Aviation were also designated in connection with Mahan Air.

OFAC has also designated Iraj Ronaghi and Touraj Zanganeh, two Iranians, “for acting for or on behalf of designated Iranian airline Meraj Air, as well as one Iran-based company that is owned or controlled by these individuals and that acts for or on behalf of Meraj Air,” an Iranian government airline. Meraj Air was used to ferry illicit cargo, including weapons, from Tehran to the Syrian regime since at least 2013.

This is the second designation in two days. On Tuesday, the Treasury Department sanctioned five Iranians it said had provided Yemen’s Iran’s-backed Houthi rebels with missiles that were used to launch attacks on cities and oil infrastructure in Saudi Arabia.

“The United States will not tolerate Iranian support for Huthi rebels who are attacking our close partner, Saudi Arabia. All countries in the region should be on guard to prevent Iran from sending its personnel, weapons, and funds in support of its proxies in Yemen,” Mnuchin said.

Adelle Nazarian is a politics and national security reporter for Breitbart News. Follow her on Facebook and Twitter.