A Ukrainian airliner crashed and burst into flames shortly after take-off from Tehran early on Wednesday, killing all 176 people on board.
Debris and smouldering parts from the Boeing 737, which carrier Ukraine International Airlines said was last serviced two days ago, were strewn across a field southwest of the Iranian capital as rescue workers with face masks retrieved bodies.
Among the victims were 82 from Iran, 63 Canadians, 11 Ukrainians, 10 Swedes, three Germans and three Britons, Ukrainian Foreign Minister Vadym Prystaiko said. Most passengers were in transit, the airline said.
Ukraine’s embassy in Iran said the causes of the crash had not been disclosed and any previous comments were not official. An embassy official said Iranian authorities had asked it to rescind an earlier statement from Iran based on preliminary information that had blamed the accident on engine failure.
Iranian TV said the crash was due to unspecified technical problems, and Iranian media quoted a local aviation official as saying the pilot did not declare an emergency.
It was Kiev-based Ukraine International Airlines’ first fatal accident. The carrier said it was doing everything possible to confirm the cause, and the investigation would also involve Boeing and national authorities.
Under international rules Iran has responsibility for investigating the crash.
Iranian state broadcaster IRIB said one of the plane’s two black boxes had been found. Semi-official news agency Mehr quoted the head of the country’s civil aviation authority as saying Iran would not give the recorder to Boeing.
Relations between Washington and Tehran are in crisis, with Iran having launched missiles at bases housing U.S. forces in Iraq several hours before the plane crash, in retaliation for a U.S. drone strike last week that killed an Iranian military commander.
Several international airlines on Wednesday suspended flights over Iranian airspace due to security risks.
Safety experts say airliner accidents are rarely triggered by a single cause and that it typically takes months of investigation to understand all the factors behind them.
Offering sincere condolences to relatives of victims, Ukraine President Volodymyr Zelenskiy said he had instructed his prosecutor general to open criminal proceedings following the crash, without specifying who they would involve.
Ukraine would test the airworthiness of its entire civilian fleet of aircraft, he added.
The plane that crashed was a three-year-old Boeing 737-800NG en route to Kiev. Its last scheduled maintenance was on Jan. 6 and there was no sign that anything was wrong before it took off from Tehran, the airline said.
A spokesman for the manufacturer, whose shares initially fell 2.3%, said it was gathering more information.
The 737-800 is one of the world’s most-flown models with a good safety record and does not have the software feature implicated in crashes of the 737 MAX. Boeing grounded its 737 MAX fleet in March after two crashes that killed 346 people.
The 737-800’s twin engines are made by CFM International, a U.S.-French venture co-owned by General Electric and France’s Safran.
Modern aircraft are designed and certified to cope with an engine failure shortly after take-off and to fly for extended periods on one engine. However, an uncontained engine failure releasing shrapnel can cause damage to other aircraft systems.
Under international rules, Ukraine would be involved in the investigation into Wednesday’s crash, and the United States would usually be accredited as the country where the jet was designed and built. France, where the engine maker CFM has half its activities, may also be involved.
There was no immediate word on whether the U.S. National Transportation Safety Board would be involved. The NTSB usually invites Boeing to give technical advice in such investigations.