An Iranian passenger plane crashed Wednesday morning near the country's northwestern city of Gazvin and 168 people on board were killed, Iran's state TV IRIB website reported.
IRIB quoted an official of the Health Ministry Mohammad Reza Montazer Khorasan as saying that all the people on board were killed, Xinhua reports.
The plane was a Russian-made Tupolev model that is not allowed to fly over western Europe.
Iranian rescuers combed through the smoldering wreckage of a Russian-made aircraft that crashed in a field near Qazvin in northern Iran.
The plane, which belonged to Iran's Caspian Airlines, was headed from Tehran to the Armenian capital Yerevan.
Iran 's civil aviation authority spokesman Reza Jafarzadeh told English-language Press TV the plane crashed 16 minutes after takeoff from Tehran's Imam Khomeini Airport, Voice of America reports.
Before crashing, the plane's tail was on fire as it circled in the air, one witness told The Associated Press.
"Then, I saw the plane crashing nose-down. It hit the ground causing a big explosion. The impact shook the ground like an earthquake. Then, plane pieces were scattered all over the agricultural fields," Ali Akbar Hashemi, a 23-year-old who was laying gas pipes in a nearby home, told AP by phone, The Associated Press reports.
Meanwhile the semi-official Mehr news agency listed the names of 153 passengers and 15 crew members. At least 42 of the names appeared to be Armenian, but it was not clear if they were from the former Soviet republic or if they were ethnically Armenian citizens of Iran, CNN reports.
The choice of the city of Helsinki is not incidental as the capital of Finland had hosted US-Soviet negotiations on the limitation of nuclear stockpiles in 1969