Prime Minister Justin Trudeau says intelligence from multiple sources indicates that an Iranian missile downed the Ukraine International Airlines flight that crashed near Tehran on Wednesday.
He says the strike might have been unintentional.
The crash killed all on board, including 138 people who were headed to Canada.
At least 63 people on the plane were Canadian citizens.
Trudeau started the news conference by offering his condolences to the families of those who were killed in the crash in Iran.
He then says important developments have been made, including intelligence suggesting the plane was shot down by an Iranian missile, although it may have been accidental.
Trudeau says a full investigation must be complete.
When asked if he blames the U.S. for the incident which was sparked by American killing of a Iranian commander.
Trudeau says that element will be part of the full investigation.
When asked if Iran will not cooperate with the investigation, given its full out denial of any wrongdoing, what action will Canada take -- Trudeau says decisions will be made behind closed doors.