Official Iranian sources renewed the talk that a technical defect caused the crash of the Ukrainian plane and the killing of its passengers yesterday, and refused to cooperate with the Americans in the investigation, while Canada promised to participate.

Iranian Minister of Transport, Mohammad Islami, said that "a plane caught fire due to a technical fault, which caused it to crash," stressing his rejection of speculation on the accident.

And Ali Abedzadeh, Assistant to the Iranian Minister of Transport, said that it was not yet clear the reasons for the Ukrainian plane crash that killed all 176 people on board.

He added that his country is investigating the causes of the accident after examining the black box, and that it will not hand over this fund to the American Boeing Company, which produces the plane, stressing that the current procedures revolve around choosing the country to which Iran will send the box.

On the other hand, US Secretary of State Mike Pompeo said that his country calls for "full cooperation with any investigation into the cause of the crash" of the plane, which fell minutes after take off from Khomeini airport in Tehran.

"The United States will continue to follow this incident closely and is ready to provide all possible assistance to Ukraine," he added in a statement. He also expressed his condolences to the families of the victims.

A Canadian security source - who asked not to be named - said that the initial estimates of Western intelligence agencies indicate that the plane did not crash due to a missile, but rather a technical failure.

In turn, Canadian Prime Minister Justin Trudeau announced that his government will work with its international partners to ensure a thorough investigation into the accident, expressing his sorrow for the killing of 63 Canadians.

For his part, Ukrainian President Volodymyr Zelinsky said that the government is studying several possible causes behind the plane crash, adding that he will speak on the phone with Iranian President Hassan Rouhani to enhance cooperation in the investigation.

Zelinsky called on his people to stop speculation and conspiracy theories regarding the plane crash, and today announced a national mourning.

Rescue teams did not find any survivors (Anatolia Agency)

Initial report
The Iranian Civil Aviation Authority said that the preliminary report of the Ukrainian plane crash shows that the plane encountered a technical problem before the crash, and that it disappeared from radar screens when it reached an altitude of 2,400 meters.

The report added that the pilot of the plane did not make a wireless communication informing him of an unusual situation, and that the plane, which was initially heading west to exit the airport area, turned to the right after it faced a problem to return to the airport before it crashed.

According to the report, the plane caught fire shortly before it crashed, and witnesses on the ground said they saw the plane flying high and the fire was burning.

The commission stated that the two recording devices were damaged, and that Iranian investigators had sent preliminary information about the accident to Ukraine, the United States, Sweden and Canada.

According to Ukrainian sources, the victims were 82 Iranians, 63 Canadians, 11 Ukraine, 10 Swedes, three Germans and three Britons, all of whom were killed.