10:32

Graham Braithwaite, professor of safety and accident investigation at Cranfield University, has said the Iranian handling of the crash site, including the apparent quick removal of evidence, raised “serious concerns over the integrity of the investigation”.



“Where you have flight recorders that tell you what has happened you can move quickly to clearing the site,” he said. “But if the recorders are damaged [as the Iranians have said] then all you have is the forensic evidence at the site to tell you the story.”

Photographs taken the day of the crash showed heavy machinery being used to move larger pieces of debris. Iranian media outlets also published several photos and videos of the wide field of wreckage and personal belongings left by the crash.

It was unclear whether the removal of the debris was done in accordance with crash-investigations procedures to ensure important evidence is preserved.

Braithwaite, who teaches a course in air accident investigations, said he was surprised that the Iranians had moved to clear the crash site before other interested parties, including Ukrainian, Canadian and other technical investigators had been able to make their own examination, which he said he would have been expected under annex 13 of the Chicago convention, the international agreement that sets out protocols for crash inquiries.