Prime Minister Justin Trudeau says intelligence now indicates the Ukrainian passenger aircraft that crashed outside of Tehran on Wednesday, killing everyone on board — including 138 people destined for Canada — was shot down by an Iranian missile.

"We have intelligence from multiple sources, including our allies and our own intelligence. The evidence indicates that the plane was shot down by an Iranian surface-to-air missile," he said during a news conference in Ottawa, adding that it might have been an unintentional act.

"The news will undoubtedly come as a further shock to the families who are already grieving in the face of this unspeakable tragedy."

Of the 176 victims killed, 63 were initially thought to be Canadian citizens and included entire families, academics, students and newlyweds. (The government on Friday revised the number of Canadian citizens among the victims to 57, following verification, although the total number of victims remained at 176.)

Watch | Video of purported missile strike:

Video recording appears to show a missile making impact on an aircraft over Tehran. The New York Times says visual and sonic clues in the footage match flight path information and satellite imagery of the area near where Flight PS752 crashed. (Video courtesy of the New York Times) 0:20

Trudeau said intelligence and evidence started coming in overnight suggesting the aircraft likely was brought down by a surface-to-air strike, but wouldn't offer further details.

The prime minister's comments came after reports out of the U.S. said it's "highly likely" that an Iranian anti-aircraft missile inadvertently brought down Ukraine International Airlines Flight PS752.

Iranian officials have denied the allegation.

"Scientifically, it is impossible that a missile hit the Ukrainian plane, and such rumours are illogical," Ali Abedzadeh, the head of Iran's Civil Aviation Organization, was quoted as saying by the semi-official ISNA News Agency on Thursday.

The crash happened just hours after Iran launched a ballistic missile attack on Iraqi bases housing U.S. soldiers, in response to U.S. President Trump's decision to order the targeted killing of Iranian military commander Qassem Soleimani.

Prime Minister Justin Trudeau attends a candlelight vigil in Ottawa Thursday for victims of the crash. (Adrian Wyld/The Canadian Press)

When asked if the U.S. airstrike was in part to blame for the crash, Trudeau said only that Canada needs a thorough investigation.

"The evidence suggests that this is the likely cause but we need to have a full and complete and credible investigation to establish exactly what happened. That's what we are calling for and that's what we're expecting will happen," he said.

Questions about investigation

Yesterday, Trudeau told reporters it was "too early to speculate" on whether the Boeing 737-800 passenger plane had been shot down. This morning, news began to break from U.S. sources citing satellite data and saying the aircraft most likely was shot down inadvertently.

Canada's signal intelligence agency said it's playing a role in the investigation.

"Although the Communications Security Establishment does not comment on intelligence operations, we can confirm that we are engaged with our national security and intelligence partners and other Government of Canada departments on this matter," said a spokesperson in an email to CBC.

According to sources, senior officials from the Privy Council Office, Transport Canada, the Department of National Defence and Public Safety met this morning to discuss the crash.

Watch | 'Canadian officials must immediately be granted access to Iran':

Prime Minister Justin Trudeau says he wants Iran to grant Canada access to the full investigation into the causes of the downed Ukrainian airliner 0:42

Trudeau vowed Canadian investigators would get access to the crash site.

Following international protocol, Iran's civil aviation authority officials will lead the investigation into the crash, while Canada's Transportation Safety Board has appointed a Canadian expert to receive and review information from the probe.

"Canadian expertise when it comes to air tragedies, expertise when it comes to crash investigations, is world class. We have much to contribute and we have lost much in the loss of so many Canadian lives, so many families across this country grieving," said the prime minister.

"We will be involved. We will offer all the expertise we have to offer."

Foreign Affairs Minister François-Philippe Champagne said today that despite Canada's rocky relationship with Iran, he's been reassured that Canadian investigators will get visas to enter the country.

Francois-Philippe Champagne told reporters in Montreal on Thursday afternoon about his conversation with the Iranian Foreign Minister 1:56

Champagne spoke to his Iranian counterpart late last night and, according to an official readout of the call, stressed "the need for Canadian officials to be quickly granted access to Iran to provide consular services, help with identification of the deceased and take part in the investigation of the crash."

Watch: Trudeau says a full understanding of the crash is required

Trudeau says his government 'will not rest' until it gets answers about what brought down the airliner that took 63 Canadian lives 0:28

The readout didn't say whether Iranian Foreign Affairs Minister Mohammad Javad Zarif agreed to Champagne's requests.

But at a press conference Thursday afternoon, Champagne described the conversation as "open" and "encouraging."

"This is step one, getting access in the country for our quick reaction team, and obviously being able to participate in the investigation," he said.

"We are following that, I would say, minute by minute or hour by hour and we will be providing all of the information to Canadians as soon as I have news."

The Iranian aviation authority said it has invited "all the states involved " to join a growing team investigating the plane crash.

Difficulty repatriating Canadian victims

The work of probing the cause of the crash and repatriating the bodies of the Canadians likely will be complicated by the fact that Canada severed diplomatic ties with Iran years ago.

Under then prime minister Stephen Harper, the federal government cut ties with Iran in 2012. The Liberals pledged to re-engage with the country in 2015 but, to date, bilateral relations have not been renewed.

Thomas Juneau, a University of Ottawa expert on the Middle East, said another hampering factor is that Iran does not recognize dual citizenship.

The Canadian government already has said that many of the dead may have been Canadian-Iranians travelling on Iranian passports. In the view of the Iranian government, those individuals could be seen as Iranians, said Juneau.

The Embassy of Canada to Turkey in Ankara has consular responsibility for Iran, while Italy represents Canada diplomatically in Tehran.

Debris of the Ukraine International Airlines plane that crashed after taking off from Iran's Imam Khomeini airport is seen on the outskirts of Tehran on Jan. 8, 2020. (Nazanin Tabatabaee/WANA/Reuters)

Ukrainian Ambassador to Canada Andriy Shevchenko said his country, which has a diplomatic presence in Iran, will do everything it can to keep Canada involved in the investigation and help it diplomatically if needed.

"We will have to walk through this pain together with Canada," said Shevchenko on Thursday, while opening up a book of condolence at the embassy in Ottawa.

"There is no long distance for pain and for empathy."

Watch: Ukrainian ambassador offers to assist Canada in Iran

Ukraine's Ambassador to Canada Andriy Shevchenko says that his country, which has a diplomatic presence in Iran, will do everything it can to keep Canada involved in the investigation into the deadly plane crash, as well as to help diplomatically with Iran if needed. 1:33

Shevchenko, who also serves as his country's representative with the Montreal-based International Civil Aviation Organization, said Ukraine already has investigators on the ground.

British Prime Minister Boris Johnson said he'll also push for an open investigation.

"We are working closely with Canada and our international partners and there now needs to be a full, transparent investigation," said Johnson, whose country lost four citizens in the crash.





"It is vital that there should be an immediate and respectful repatriation of those who've lost their lives to allow their families to grieve properly."



Champagne will meet with U.K. Foreign Secretary Dominic Raab later this afternoon in Montreal. They're expected to talk about the crash and mounting tensions in the Middle East.

"Sad to arrive under such tough circumstances as our close friend Canada grieves for those who died tragically in yesterday's Ukrainian International Airlines crash," tweeted Raab before taking off for Montreal.

Watch: 'I think it is too soon to be drawing conclusions,' Trudeau says.