Iranian state TV said mechanical issues are suspected after the Boeing 737 crashed after takeoff.
A Ukrainian airplane thought to have at least 167 people aboard crashed after takeoff in the Iranian capital of Tehran on Wednesday, Iranian state TV reported.
There was no immediate word of casualties from the crash, which has not been confirmed by NBC News. Rescuers were forced to pause efforts because of the fire at the crash site, according to Iranian reports.
The plane had taken off from Imam Khomeini International Airport, the report said. The crash is suspected to have been caused by mechanical issues, it added, without elaborating.
Civil aviation spokesman Reza Jafarzadeh said an investigation team was at the site of the crash on the southwestern outskirts of Tehran, according to the AP.
Iranian state TV reported that officials got word of the crash just before 6:30 a.m., and it involved a Boeing 737. It had previously reported that 180 people were on board.
"We are aware of the media reports out of Iran and we are gathering more information," Boeing said in a statement.
The Pentagon said Iran launched more than a dozen ballistic missiles at U.S. and coalition forces in Iraq early Wednesday local time.
The Federal Aviation Administration on Tuesday night issued "notices to airmen" outlining flight restrictions in the region.
The FAA said that it prohibited U.S. civilian aviation operators from flying in the airspace over Iraq, Iran and the waters of the Persian Gulf and Gulf of Oman. The agency said it was closely monitoring events in the Middle East.