An Iranian company has displayed four U.S.-made helicopters it says were purchased through third parties.

The display of the R-44 helicopters came during an air exhibition in Kish Island, in the Persian Gulf.

The four-person helicopters are manufactured by the California-based Robinson Helicopter Company.

Mahmoud Azin, the head of Iran's Helicopters Company, told the Tasnim news website on Thursday that the helicopters were purchased at a marked-up price through "dealers" and can be used for both training and police air patrol.

Iran is under crippling international sanctions linked to the dispute over its nuclear program.

The company, which has some 25 helicopters, mainly services Iranian oil sites.