Here's everything we know so far about the crash involving a Ukraine International Airlines Boeing 737 in Iran
- A plane carrying 176 people crashed just minutes after takeoff in Iran, killing everyone on board.
- The Ukraine International Airlines plane was just three years old, and had recently been tested, but authorities have distanced the incident from terrorism as tensions heighten between the US and Iran.
- But Ukraine's embassy in Tehran appeared to delete an earlier statement that totally dismissed the idea of terrorism or a rocket attack, replacing it with one that says the cause is unknown and is being investigated.
- The plane appeared to burst into flames in mid air, and authorities in Ukraine and Iran will investigate. But the American plane manufacturer Boeing may have trouble dealing with Iran and may face further scrutiny after other fatal crashes.
- Here is everything we know, from the timeline, to the victims, to the possible causes, and how investigations into the crash could work.
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A Ukraine International Airlines plane crashed in Iran early on Wednesday morning, killing all 176 people on board in what authorities are initially attributing to a technical issue.
Investigations will be conducted into what caused the crash, and Ukraine's embassy has already changed its account.
But officials have have largely been consistent in distancing it from the possibility of terrorism - particularly relevant amid heightened tensions in Iran after the US assassinated its top general and Iran subsequently attacked bases housing US troops in Iraq.
The plane appeared to burst into flames in the air, videos posted on social media showed.
People of seven nationalities were killed in the crash, in an incident that could pile further scrutiny on its manufacturer, Boeing, which is already dealing with the fallout from two fatal crashes by a different plane model.
This is what we know so far.
The plane appeared to bust into flames and crashed less than 10 minutes after takeoff.
A Ukraine International Airlines Boeing 737-800 NG took off from Iran's Tehran Imam Khomeini International Airport at 6.12 a.m. local time on Wednesday, according to flight tracking website FlightRadar24.
Flight PS 752 was bound for Kiev, Ukraine, but lost contact two minutes after taking off, FlightRadar24 recorded.
167 passengers and nine crew members were on board.
A video, which was shared by state-run media outlet the Iranian Students' News Agency, appears to show the plane on fire in the air before hitting the ground and filling the sky with flames. The video's content and connection to this crash has not yet been confirmed.
Debris and engine parts ended up strewn across a field around six miles (10 kilometers) from the airport, Reuters reported. Reuters quoted the head of Iran's emergency services, Pirhossein Koulivand, as saying that the flames were "so heavy" that 22 ambulances, four bus ambulances, and a helicopter could not "do any rescue."
The time of the crash is not yet known, but the short distance between the plane and the airport shows that it was just minutes after takeoff.
Investigators will now look into the cause of the crash.
The cause of the crash is still unknown, but officials are distancing it from terrorism
Both Ukrainian and Iranian authorities said in the hours after the crash that it had been caused by technical problems, dismissing the idea that it could have been a terrorist attack.
Ukraine's embassy in Tehran initially dismissed the idea of terrorism or a rocket attack, The Independent reported. But that statement has since been replaced by one that says the cause is unknown and is being investigated.
Qassem Biniaz, an official at the Iranian Ministry of Roads and Urban Development, told government news agency IRNA that an engine caught fire and the pilot was unable to regain control, The New York Times reported.
Ukraine International Airlines said the plane was new and recently checked.
It said in a statement that the plane was built in 2016 and had been delivered to the airline directly from Boeing. It said that the last scheduled maintenance of the plane had taken place just two days before the crash. The airline also said that its crew was experienced.
The airline has never had a fatal crash before.
The victims came from seven counties, with most from Iran and Canada.
Ukraine's foreign minister Vadim Prystaiko said the victims included 82 Iranians, 63 Canadians, and 11 Ukrainians.
Prystaiko also said there were 11 Swedish citizens, four Afghan citizens, three UK citizens, and three German citizens on the plane.
Photos from the crash site show passenger belongings, including clothes and books, as well as body bags.
Ukraine International Airlines said it will post the passenger list on its website "after final confirmation of their presence on board of the aircraft."
Investigations have started but may be hampered by international tensions, and Boeing may feel the pressure
Iranian state broadcaster IRIB said one of the plane's two black boxes had been found. Under international rules, Iran must investigate the crash.
Ukraine's President, Volodymyr Zelensky, cut short a trip to Oman to return to Ukraine and said that he had instructed his prosecutor general to open criminal proceedings after the crash.
Ukraine International Airlines said it will take "all measures" to determine the cause of the crash.
It said that Ukraine, Iran, Boeing representatives and Ukraine's Bureau of Air Accidents Investigation would also be involved.
But The Guardian reported that Boeing may face problems in getting involved with the investigation due to US sanctions on Ukraine - and heightened tensions between the countries after the US assassinated Maj. Gen. Qassem Suleimani.
Mehr, a semi-official news agency in Iran, quoted the head of Iran's civil aviation authority as saying the country would not give the black box to Boeing, Reuters reported.
Boeing might also face more scrutiny as it still deals with the aftermath of two fatal crashes by its 737 Max planes, which killed 346 people. The Max planes use different software to the 737 plane that crashed in Iran.
Boeing said in a statement early on Wednesday: "We are aware of the media reports out of Iran and we are gathering more information."
It said later on Wednesday: "This is a tragic event and our heartfelt thoughts are with the crew, passengers, and their families. We are in contact with our airline customer and stand by them in this difficult time. We are ready to assist in any way needed."
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