An Iranian military plane crashed early on Monday at Tehran's Mehrabad airport killing 38 people including 35 members of the Revolutionary Guards, state television reported.
There were no survivors when the Antonov 74 aircraft crashed shortly after takeoff, the director of the airport told the TV channel.
The plane was heading for Shiraz in the south of Iran, the television said.
Iran's Revolutionary Guards are the Islamic regime's ideological army.
Mehrabad international airport is used for civil and military purposes. It is situated in a western district of the capital.
Last December an army Lockheed C-130, bought from the United States before 1979, crashed in a Tehran suburb after takeoff killing its 108 occupants, many of them journalists.
Iran's civil and military fleet is made up of ancient aircraft in terrible condition due to their age and lack of maintenance.
The Iranian regime is barred by sanctions from buying American Boeing planes or European Airbus craft when they include a significant number of US parts.