Ukrainian jet 'trying to turn back' when it crashed, Iranian report claims

The findings come as speculation grows over the tragic incident, with some aviation intelligence groups claiming the jet may have been shot down or hit by a missile.

"The plane, which was initially headed west to leave the airport zone, turned right following a problem and was headed back to the airport at the moment of the crash," the Iranian Civil Aviation Organisation said on its website late Wednesday, reporting the first findings into the incident.

"The plane disappeared from radar screens the moment it reached 8,000 feet (2,400 metres). The pilot sent no radio message about the unusual circumstances," the group added.

Eyewitnesses on the ground and on board an aircraft flying above the Ukrainian Boeing 737 reported seeing a fire on board the plane, "which grew in intensity", the statement added.

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The fire caused the plane to explode upon landing, likely due to the plane being fully loaded with fuel for the flight to Kyiv, Ukraine.

The report confirmed that both of the plane's black boxes - which store crucial data about the aircraft's movements - had been recovered, although there was some damage to their memory. Iranian authorities declared yesterday they would not hand over boxes to its manufacturer Boeing.

Meanwhile, a leading aviation group has said "obvious projectile holes" in the wreckage indicate the jet had been shot down.

Ukrainian President Volodymyr Zelensky, said a team of 45 crash investigators from his country had arrived in Iran to assist in the probe, saying he expects them to be present at the black box inquiry.

He also said he planned to call Iranian President Hassan Rouhani about the crash and the investigation.

"Undoubtedly, the priority for Ukraine is to identify the causes of the plane crash," Zelensky said. “We will surely find out the truth.”

Ukraine has in the meantime halted all flights to Iran and  advised its citizens against travel there.

Agencies contributed to this report.