Two badly damaged black box flight recorders have been recovered from an Iranian airliner that crashed and killed all 168 people on board, official media said on Thursday.
The cause of Wednesday's crash, the worst in Iran for six years, was still unknown, state English-language Press TV said.
The Russian-built Tupolev aircraft was en route to neighboring Armenia when it caught fire in mid-air and plowed into farmland 16 minutes after departing Tehran.
The Caspian Airlines plane exploded on impact and scattered incinerated metal and the bodies of 153 passengers and 15 crew across a wide area around a deep smoking crater gouged into the ground.
Press TV's website quoted an official as saying the two boxes, which could contain vital clues to explaining the crash, were heavily damaged but that experts were trying to retrieve data from them.
Authorities were still searching for a third black box, the semi-official Fars News Agency said.
Most of those on board were Iranians, but there were also Armenian and Georgian citizens.
Deputy Transport Minister Ahmad Majidi said DNA testing would be needed to identify the remains. Eight members of Iran's national junior judo team and two coaches were among the dead.
All gathered parts of dead bodies scattered in the crash area have been handed over to Qazvin's coroner office and will be transferred to Tehran's coroner office today, he said.
About 40 relatives and friends of the victims plan to fly from Yerevan to Tehran on Thursday, Caspian Airline official Arlen Davudyan told Reuters at Yerevan Airport.
Most of them were dressed in black. It was not clear whether they would continue to the crash site north of Tehran.
I lost by best friend. He was almost a brother ... I'm flying to Tehran to pay my condolences to his wife and kids. said Mehdi Sohrabi, a 27-year-old Iranian who studies in Armenia.
Fina Karapetian, an Armenian in her 30s, said her sister and two nephews, 11 and 6, were on board the Tu-154 plane.
Her husband cried on telephone, 'How will I live without them.' He has no more family, she said. My mother and father have almost gone out of their minds.
OLD FOE OFFERS CONDOLENCES
The United States, the Islamic Republic's arch foe, extended condolences on Wednesday to families of the victims.
Washington has no diplomatic ties with Tehran but has been trying to reach out to the country as part of an effort to coax it into negotiations over its disputed nuclear program.
The United States extends it condolences to the families of those who lost their lives in today's crash of a Caspian Airlines plane carrying passengers from Tehran, Iran to Yerevan, Armenia, State Department spokesman Ian Kelly said.
U.S. sanctions bar the sale of Boeing aircraft to Iran and hinder it buying other aircraft or spares from the West, many of which rely on U.S.-built engines and parts. Instead, Iran has turned to buying and leasing Russian-made craft.
Air safety experts have said Iran has a poor record, with a string of crashes in the past few decades, many involving Russian-made aircraft. It was the third deadly crash of a Tupolev Tu-154 in Iran since 2002.
It was the deadliest crash since 2003 when an Ilyushin Il-76, also Russian built, crashed into an Iranian mountain.
Tehran-based Caspian Airlines was set up in 1993 and flies an all-Tupolev fleet linking Iranian cities and also routes to the United Arab Emirates, Ukraine and Armenia.