TEHRAN, IRAN - Hours after Iran's ballistic missile attack on two U.S. air bases in Iraq, a deadly plane crash in Iran killed all 176 passengers on board.

According to the BBC, the victims were aboard a Ukrainian Boeing-737, most of them from Iran and Canada.

The plane was headed to Kiev, Ukraine and went down shortly after taking off from Imam Khomeini in Tehran at about 8:42 p.m., Tuesday (CMT). 

Ukraine's Tehran embassy initially blamed engine failure, but later retracted this statement. 

It said any comment regarding the cause of the accident prior to a commission's inquiry was not official.

Iranian media claimed technical problems and quoted an aviation expert who said no emergency had been declared. 

Debris and engine parts from the plane were discovered as far as six miles from the airport and rescue workers with face masks were seen searching the wreckage for victims. 

Among those killed were 82 Iranians, 63 Canadians, 11 Ukrainians including all nine crew members, ten Swedes, four Afghans, three Britons, and three Germans.

Ukrainian President, Volodymyr Zelensky, said he was cutting short a trip to Iman in favor of flying back to Kiev to address the devastating crash.

He warned against "speculation or unchecked theories regarding the catastrophe" until official reports are released. 

In a statement, the Ukrainian president said, "My sincere condolences to the relatives and friends of all passengers and crew."