Iran is not conducting its probe into the downing of a civilian airliner in January properly and many questions remain unanswered, an independent Canadian report into the tragedy said on Tuesday.\r\n\r\n\r\n\r\nThe 79-page document is the latest expression of frustration from Western nations into how Tehran is handling the aftermath of a disaster that claimed 176 lives.\r\nIran\u2019s Revolutionary Guards say they accidentally shot down the Ukraine International Airlines plane shortly after take off, mistaking it for a missile when tensions with the US were high. Many of the victims were Canadian citizens or permanent residents.\r\nFormer Canadian cabinet minister Ralph Goodale, charged with helping the victims\u2019 families and examining how to deal with similar disasters in future, said \u201cmany of the key details of this horrific event\u201d remain unknown.\r\n\u201cIran bears responsibility for that because ... it has not conducted its investigations (safety, criminal or otherwise) in a truly independent, objective and transparent manner, and answers to critical questions\u201d are absent, he wrote in the report.\r\nLast month, a governing panel at the United Nations\u2019 aviation agency urged Iran to accelerate the investigation. Later in November, Ukraine said Iran was dragging its feet.\r\nIn the hours before the disaster, Iran had fired missiles at US bases in Iraq. Five days earlier, Washington had killed a Revolutionary Guards commander with a drone strike in Iraq.\r\nGoodale said Iran needed to explain how it had assessed the risks to civilian aircraft in its airspace and what it had told operators. He also said Tehran had to reveal why it had left the airspace open and also why exactly the Guards had decided to down the plane.\r\nCanada, working with other nations who lost citizens, is pressing Iran for reparations while \u201cseeking a full and candid accounting of what exactly happened\u201d and a formal apology, Goodale said.