Five people were killed when the Iranian rescue helicopter they were traveling in crashed into a utility pole in western Iran on March 4, according to state media.
The helicopter was on its way to pick up a pregnant woman in urgent need of medical care when it went down in Chaharmahal and Bakhtiari Province, state television reported.
Pirhossein Koulivand, head of the country's emergency medical services, said that three of the five people on board were flight crew and the two others were rescue workers.
The cause of the crash was unclear.
The state-run IRNA news agency reported that the helicopter collided with a transmission tower, while state TV said it had crashed into the mountains.
The Zagros mountain range, which passes through Chaharmahal and Bakhtiari Province, has been the site of several crashes in recent years.
Tehran says U.S. sanctions have long prevented it from buying new aircraft or spare parts from the West to modernize its fleet.