Jan. 10 (UPI) -- Authorities in Iran on Friday rejected out of hand the suspicions by U.S. intelligence officials that a Ukrainian jetliner that crashed this week was shot down by an Iranian missile.
Ali Abedzadeh, head of the Iran Civil Aviation Organization, told semi-official Press TV that "from a scientific viewpoint" it's "impossible that a missile hit the Ukrainian plane."
"We can say that the airplane, considering the kind of the crash and the pilot's efforts to return it to Imam Khomeini airport, didn't explode in the air," he said. "So, the allegation that it was hit by missiles is totally ruled out."
Abedzadeh on Thursday dismissed the U.S. suspicions as "illogical rumors."
Ukraine International Airlines Flight PS752, a Boeing 737-800, crashed shortly after leaving the airport in Tehran early Wednesday, killing all 176 people on board -- mostly Iranian and Canadian citizens.
Iranian investigators said in a preliminary report Thursday the plane was attempting to return to the airport and its pilots did not report an emergency to ground controllers. It also said witnesses reported the jetliner was on fire before it crashed. Officials in Tehran also said earlier a technical malfunction was the most likely cause.
Iranian officials are examining the plane's flight data and cockpit voice recorders.
"The plane caught fire three minutes into the flight, according to what the witnesses have reported and the data collected from the parts of the airplane," Abedzadeh said. "The pilot tried to return the airplane at the altitude of 8,000 feet, but due to the fire, the airplane crashed and exploded."
Canadian Prime Minister Justin Trudeau said Thursday intelligence indicates the airliner was shot down, possibly by accident, by the Iranian military -- a conclusion shared by several U.S. intelligence officials.
Ali Rabiei, a spokesman for the Iranian government, called reports the plane was shot down "a big lie."
"It is unfortunate that the psychological operation of the U.S. government, and those supporting it knowingly and unknowingly, are adding insult to the injury of the bereaved families and victimizing them for certain goals by propagating such fallacies," he said.
British Foreign Secretary Dominic Raad on Friday warned British nationals against traveling to Iran and called for "a full and transparent" investigation. The travel warning is based on the possibility of a shootdown and escalating tensions, he said.
Ukrainian President Volodymyr Zelensky said his government has not yet ruled out a missile strike, and called on Canada, Britain and the United States to submit all data they have concerning the crash.
"Our goal is to establish the undeniable truth," Zelensky said in a statement. "We consider it a responsibility of the entire international community to the families of the victims and the memory of the victims of the disaster. The value of human life is superior to any political motive."
Multiple U.S. news outlets reported Thursday intelligence officials suspect a missile downed the plane, based on satellite and radar data. The plane crashed around the same time Iran launched missile attacks against two U.S. military bases in Iraq -- retaliation for the U.S. airstrike last week that killed Iranian commander Qassem Soleimani.
U.S. President Donald Trump told reporters at the White House Thursday he isn't sure the crash was the result of mechanical trouble.
"I have my suspicions," he said. "Somebody could have made a mistake on the other side. ... Something very terrible happened."
Trump also added that the plane was flying in a "rough neighborhood" when it went down.