The crash is suspected to have been caused by mechanical issues.
Tehran: All 170 people on board a Ukrainian passenger plane that crashed Wednesday after taking off from Tehran were killed, Iran's Red Crescent said.
"Obviously it is impossible that passengers" on flight PS-752 "are alive," the head of Red Crescent told semi-official news agency ISNA, adding that 170 passengers and crew had boarded the plane.
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.
An investigation team was at the site of the crash in southwestern outskirts of Tehran, civil aviation spokesman Reza Jafarzadeh said.
Flight data from the airport showed a Ukrainian 737-800 flown by Ukraine International Airlines took off Wednesday morning, then stopped sending data almost immediately afterward, according to website FlightRadar24.
The airline did not immediately respond to a request for comment.
The crash came hours after Iran launched a ballistic missile attack targeting two bases in Iraq housing US forces in retaliation for the killing of Revolutionary Guard General Qassem Soleimani.
(With agency input)