Iran's initial report says Ukrainian plane was on fire before crash
Ukraine declares national day of mourning, president cautions against speculation
A Ukrainian airliner was on fire immediately before it crashed southwest of Tehran, killing all 176 aboard, according to an initial report by Iranian investigators.
The Ukraine International Airlines Boeing 737-800, flying to Kyiv and carrying mostly Iranians and Iranian-Canadians, crashed shortly after taking off on Wednesday from Tehran's Imam Khomeini airport.
The Ukrainian airliner took off from the Tehran airport at 6:12 a.m. local time and was given permission to climb to 7,920 metres, the report said. It crashed minutes later.
The Tehran-Toronto via Kyiv route has been popular for Canadians of Iranian descent visiting Iran, in the absence of direct flights.
Ukraine also said on Thursday its investigators wanted to search the crash site for possible Russian missile debris.
Ukrainian authorities have said those on board included 82 Iranians, 63 Canadians and 11 Ukrainians.
The bodies and remains recovered from the site of the crash have been taken to the coroner's office for identification, the report said.
The initial report by Iran's civil aviation organization cited witnesses on the ground and in a passing aircraft flying at high altitude as saying the jet was on fire while still aloft.
According to eyewitness reports an explosion resulted from the plane's impact from hitting the ground.
The three-year-old jet, which had its last scheduled maintenance on Monday, encountered a technical problem shortly after takeoff and started to head toward a nearby airport before it crashed, the report said.
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The technical problem was not specified in the report, which also said there was no radio communication from the pilot and the aircraft disappeared from radar at 2,440 metres.
It is so far not clear if any technical issue could be related to a maintenance fault or defective part.
Initial assessment of Western intelligence agencies was the plane had suffered a technical malfunction and had not been brought down by a missile, five security sources — three Americans, one European and the Canadian — who asked not to be named, told Reuters.
Judson Rollins, managing partner with Propel Aviation Solutions, told CBC's The National that the plane fell too quickly for the mechanical difficulties theory to make sense.
"Typically with an engine failure you don't see that kind of structural falling apart, if you will. You tend to see a more gradual failure of systems. And in this case, what we've seen is the information just stopped appearing."
WATCH: See what we know about the crash — and get a sense of how the probe will unfold.
However, other aviation experts aren't ruling out the mechanical failure scenario yet, with investigators examining the 737's turbines, which belong to the same family as the ones that had metal fatigue problems. A Southwest air passenger was killed after a piece of a 737 turbine snapped off midair in 2018.
The disaster puts a renewed spotlight on Boeing, which faces a safety crisis over a different type of 737, though the plane that crashed in Iran does not have the feature thought to have caused crashes of the grounded 737 MAX.
The initial Iranian report referred to the crash as an "accident."
Investigations into airliner crashes are complex, requiring regulators, experts and companies across several international jurisdictions to work together. Issuing an initial report within 24 hours is rare and it can take months to fully determine the cause.
Ukraine names crash theories
The crash happened hours after Iran launched missile attacks on U.S.-led forces in Iraq, leading some to speculate that the plane may have been hit by a missile. In Kyiv, Ukraine's President Volodymyr Zelensky said the government was considering several possible causes of the plane crash.
Oleksiy Danylov, Ukraine Security Council secretary, said the country's investigators wanted to search for possible Russian missile debris after seeing information about it on the internet.
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He referred to an unverified image being circulated on Iranian social media purportedly showing the debris of a Russian-made Tor-M1 surface-to-air missile of the kind used by the Iranian military.
In western social media, the missile attack theory gained traction after images were posted apparently showing shrapnel holes in the wreckage of the aircraft's fuselage.
Giancarlo Fiorella, an investigator with global investigative group Bellingcat, told CBC News the suspected holes were in fact rocks that had come to rest on the sheets of torn metal.
"What we were able to do was to find higher-resolution images of the same piece of wreckage from other sources," Fiorella said.
Ukraine is looking at various possible causes of the crash, including a missile attack, a collision, an engine explosion or terrorism, Danylov wrote on social media.
Our [investigative] commission is talking to the Iranian authorities about visiting the crash site and is determined to search for fragments of a Russian Tor air defence missile about which there was information on the internet," Danylov separately told Ukrainian news site Censor.net.
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Ukrainian investigators into the crash include experts who participated in the investigation into the 2014 shooting down of Malaysian Airlines flight MH17, Danylov said
The Malaysian airliner was shot down on July 17, 2014, over territory held by pro-Russian separatists in eastern Ukraine as it was flying from Amsterdam to Kuala Lumpur, killing all 298 people aboard.
In a television statement, Zelensky asked people to refrain from speculation, conspiracy theories and hasty evaluations regarding the crash. He also declared Thursday a day of national mourning.
He said he would speak by telephone with the Iranian president to step up co-operation into investigating the reason for the crash.
'Canadians have many questions'
Canadian Foreign Minister Francois-Philippe Champagne called his Iranian counterpart to stress the need for Canadian officials "to be quickly granted access to Iran to provide consular services, help with identification of the deceased and take part in the investigation of the crash," a Canadian statement said.
"Canada and Canadians have many questions which will need to be answered."
Zelensky, in a phone call with U.K. Prime Minister Boris Johnson, invited Britain to join the investigation, Zelensky's office said.
"Boris Johnson supported this idea and stressed that the best British experts should be involved in finding out all the circumstances of the tragedy," it said.
As the country where the plane was designed and built, the United States would usually be allowed to be accredited, but neither side has said whether U.S. investigators will be dispatched to Iran.
Iran's aviation body could not be reached for comment to clarify its position.