BA Boeing Co

By Aresu Eqbali in Tehran, Rory Jones in Dubai and Georgi Kantchev in Moscow 

The Ukraine International Airlines flight that crashed after takeoff from Tehran was on fire before it hit the ground, according to Iran's aviation regulator, adding a new clue for investigators seeking to determine what caused the plane to go down.

The Boeing Co. 737-800 single-aisle jet ascended to 8,000 feet before disappearing from radar and crashing, killing all 176 people on board, Ali Abedzadeh, head of Iran's Civil Aviation Organization said, according to the country's state news agency.

The plane was aflame as its hit the ground and exploded, Mr. Abedzadeh said, citing witnesses on the ground and a flight crew on another aircraft at a higher altitude. It wasn't immediately clear what caused the fire and if that led to the crash.

The investigation is expected to be one of the most politically thorny probes ever. Tensions are high between the U.S. and Iran over the killing of a top Iranian general. Boeing is already dealing with the fallout from the grounding of its 737 MAX fleet after two fatal crashes involving that jet.

Boeing said it is in contact with Ukraine International Airlines and is ready to assist in any way. The U.S. State Department said it is prepared to offer Ukraine all possible assistance and called for cooperation in the investigation.

No radio messages were received from the pilot about unusual conditions, Mr. Abedzadeh added in an initial report, according to IRNA, the state news agency.

The Ukrainian government said Thursday that investigators were considering several possible causes of the crash.

A team of 45 Ukrainian experts and officials arrived in Tehran in the early hours of Thursday and will be involved in decoding the plane's black boxes and identifying and repatriating bodies. The team has already collected DNA samples from relatives of the victims in Ukraine.

"The priority for Ukraine is to establish the causes of the crash," President Volodymyr Zelensky said in a video posted on his official Facebook page Thursday. "To do this, a detailed and independent investigation will be carried out in accordance with international law."

Write to Rory Jones at rory.jones@wsj.com and Georgi Kantchev at georgi.kantchev@wsj.com

(END) Dow Jones Newswires

January 09, 2020 03:40 ET (08:40 GMT)

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