Canada’s Prime Minister Justin Trudeau declared January 8 a national day of remembrance for victims of air disasters on the anniversary of the downing of Ukraine flight PS752 by Iran. A total of 176 people were on board the flight that took off from Tehran’s Imam Khomeini International Airport at 6.12am local time. Minutes later it crashed. After initially denying any involvement, Iran admitted it had accidentally shot down the plane. The Iranian regime blamed the tragedy on human error and a misaligned surface-to-air missile. Fifty-five Canadians and 30 permanent residents were on board. It was one of the worst air disasters in Canadian history and prompted national outrage. One year on, families are still searching for answers. “Air disasters have taken the lives of too many Canadians and left too many families across our country without loved ones,” Mr Trudeau said. “Today, on the first National Day of Remembrance for Victims of Air Disasters, I join Canadians across the country to remember and honour the people who were lost in these tragedies and mourn alongside those they left behind.” The five nations whose citizens died announced on Friday they would hold Tehran to account and ensure it paid full compensation to <a href="https://www.thenationalnews.com/world/the-americas/grieving-relatives-harassed-by-iranian-officials-over-downed-jet-campaign-1.1138420">bereaved families</a>. Tehran said two of its surface-to-air missiles brought down the Ukraine International Airlines flight by mistake on January 8 last year, killing all passengers and crew on board. <a href="https://www.thenationalnews.com/world/mena/families-of-those-killed-in-plane-shot-down-by-iran-threatened-and-harassed-1.1129493">The incident came during a period of heightened tension</a> with the US and followed a missile attack only hours earlier that had injured American soldiers in Iraq. Iran’s investigation into the crash near Tehran has been marked by delays, incomplete accounts and blame-shifting with a full report on the circumstances of the tragedy still to be published, in a breach of international aviation rules. Ukrainian officials confirmed this week they received a preliminary report on December 31 and had 60 days to assess its findings before publication. The International Co-ordination and Response Group for the victims, comprising Canada, the UK, Ukraine, Sweden and Afghanistan, said it remained committed to holding those responsible to account. “Today we honour the memory of those who perished and offer our sincere condolences to all who mourn the victims of the PS752 tragedy,” said the group. “We share the grief of the families, relatives and friends who lost loved ones. We urgently call on Iran to provide a complete and thorough explanation of the events and decisions that led to this appalling plane crash. “Our countries will hold Iran to account to deliver justice and make sure Iran makes full reparations to the families of the victims and affected countries.” Tehran has accepted blame and said it would give $150,000 to each of the families of the victims, but the offer was dismissed by Ukraine. In 1996, Washington agreed to pay a total of $61.8 million to the families of 290 people killed in an Iran Air plane shot down by a US warship in 1988. After its 2003 admission of responsibility for the 1988 Lockerbie bombing of a US-bound passenger plane, Libya paid $2.7 billion to the families of the 270 people killed. Iran's failure to properly investigate the event 12 months ago means it is unsafe for aircraft to fly over Iran, Ralph Goodale, the Canadian government's key adviser on the disaster told <em>The National</em>. Mr Goodale said a similar incident could “happen again tomorrow” because of the lack of a thorough and transparent inquiry. He said all options open to Canada remain on the table, including sanctions targeting prominent Iranians under the country’s version of Magnitsky laws aimed at punishing state-backed abusers of human rights. Meanwhile, UN investigator Agnes Callamard said the downing of the jet underscored the need for tighter rules on shutting down airspace amid military tensions and for investigating air tragedies sooner.<br/> Authorities are loath to shut down air routes for political and financial reasons during moments of heightened tension, such as those that arose in January between the US and Iran after the assassination of an Iranian military commander, Ms Callamard said.<br/> "Passengers and flight crew cannot be left at the mercy of states and airlines who put revenue and other motives ahead of safety," she said. She called for the creation of a new body “completely independent” of governments and airlines to monitor air routes near conflict zones, to share information of threats and “prevent future incidents and save lives”.