Relatives of victims who died in a plane crash in January when an aircraft was accidentally shot down by Iran's Islamic Revolutionary Guard Corps have since been “threatened and harassed”, an investigation led by Canada found. The IRGC shot down a 737 aircraft minutes after it left Tehran on January 8. Of the 176 people killed, 138 had ties to Canada. Canada's police and national security agencies must investigate and follow up on the threats and harassment suffered by the grieving families, the investigation report said. The flight to the Ukrainian capital of Kiev was carrying 167 passengers and nine crew members from several countries. On board were 82 Iranians, more than 50 Canadians, including many Iranians with dual citizenship, and 11 Ukrainians. The route was popular with those travelling onward to Canada. The incident happened the same night Iran launched a ballistic missile attack on US soldiers in Iraq, in response to the American drone strike that killed senior general Qassem Suleimani in Baghdad on January 3. Iran initially denied responsibility for the crash before admitting in the face of mounting evidence and international pressure that the Boeing 737-800 was hit by two surface-to-air missiles. Canadian Prime Minister Justin Trudeau on March 31 appointed Ralph Goodale to carry out the investigation into the crash, the results of which <a href="https://www.international.gc.ca/gac-amc/publications/flight-vol-ps752/index.aspx?lang=eng#a4">were released on Tuesday.</a> The report said vital questions about the exact chain of events and decision-making were unanswered. Mr Goodale said meeting families of the victims was “profoundly emotional” because their “grief and anguish are so real and ongoing”. “They mourn the rich human potential so cruelly destroyed," he said. "They ask questions, they yearn for the truth. "All of that is powerful motivation for Canadians to remain dogged and unrelenting in our search for the transparency, accountability and justice the families need and deserve." Mr Goodale said many families of the victims were sceptical of Iran’s explanation of the crash. He lamented the fraught engagement with Iran after the incident, noting that Canada has not had an embassy or ambassador in Iran since 2012. The report said Iran would not give Canada the chance to appoint an accredited representative to the investigation, which would have provided the North American country with “more first-hand knowledge”. “Instead, despite suffering the greatest loss of life, Canada’s official role in the safety investigation was limited to that of an observer,” it said. The Transportation Safety Board of Canada will review and comment on the final safety investigation report of the Iranian regulators when it becomes available, the report said. It said a team of legal experts, led by Global Affairs Canada, was working with expert colleagues in the International Co-ordination and Response Group, made up of Canada, Ukraine, Sweden, Afghanistan and the UK, to pursue reparations from Iran. Mr Trudeau, Minister of Foreign Affairs Francois-Philippe Champagne and Minister of Transport Marc Garneau welcomed the investigation's findings. “Today, we are pleased to accept the report from special adviser Ralph Goodale, who is advising on the government of Canada’s ongoing response to Iran’s shooting-down of Flight PS752," they said in a joint statement. "We thank Mr Goodale for his dedication, heartfelt work and thoughtful recommendations.” They said the report highlighted the importance of “paying close attention to the needs of the families of victims of air tragedies, which must be at the heart of Canada’s response". “Canadians must remain steadfast in our search for the transparency, accountability and justice the families need and deserve. "The report contains important recommendations on ways to improve support for the families of victims of air disasters. "These include robust engagement with families and accurate, timely and reliable information sharing with them as quickly as possible and on an ongoing basis. "Relentless pursuit of the truth about what happened is absolutely vital. "To that end, the special adviser has posed vital questions that Iran should answer comprehensively, with supporting evidence, to demonstrate the credibility of its investigations and to convince the international civil aviation community that Iran can provide a safe airspace. “Canada continues to work with international partners to pursue thorough and credible investigations into Iran’s shooting down of this aircraft as we seek transparency, accountability and justice for the victims and their families.”