OTTAWA -- Prime Minister Justin Trudeau says Canada will continue to hold Iran to account after its military shot down a passenger jet in January 2020.

"First and foremost, we will continue to be there to support the families and fulfil our promise to find out exactly what went wrong, how this terrible tragedy could happen and ensure that Iran wields full responsibility for its role in the loss of so many lives," Trudeau told reporters in Ottawa on Friday.

A day earlier, Canada's air-safety investigator said Iranian officials failed to provide evidence that Ukraine International Airlines Flight 752 was shot down by mistake, leaving key questions unanswered as Iran's military effectively investigated itself.

The regime's civil aviation body released a final report this week that blamed "human error" for two surface-to-air missiles fired at the jetliner minutes after takeoff from Tehran on Jan. 8 last year.

The Canadian government has rejected the report outright, describing it as "incomplete" and devoid of "hard facts or evidence" on the factors that led to the death of 176 people on board, including 55 Canadian citizens, 30 permanent residents and dozens of others with ties to Canada.

The disaster unfolded hours after Iran launched missiles into Iraq at two American military bases in retaliation for the U.S. having killed top Iranian general Qassem Soleimani near the Baghdad airport by order of then-U.S. president Donald Trump.

A group representing the families is demanding Canada impose sanctions against Iran's Revolutionary Guard to pry out more information on the shootdown.

They also want Canada to take the Iranian regime to the International Court of Justice if talks stretch beyond three months.

Trudeau said Friday he will work with international partners to demand justice and transparency on behalf of Canadian families.

Britain, Ukraine, Afghanistan and Sweden also lost citizens when the plane was destroyed, and the countries formed a coalition with Canada to deal with Iran, demanding reparations and a more transparent report.

This report by The Canadian Press was first published March 19, 2021.