Qassem Soleimani

Canada's Transportation Safety Board says Iranian officials failed to provide evidence that a passenger jet was shot down by mistake early last year, leaving key questions unanswered as Iran's military effectively investigated itself.

Canada's special adviser on the Iranian military's downing of a passenger jet one year ago this week is rejecting Tehran's offer to pay $150,000 to the families of those killed in the tragedy.

A leaked recording of an exchange between an Iranian air-traffic controller and an Iranian pilot purports to show that authorities immediately knew a missile had downed a Ukrainian jetliner after takeoff from Tehran, killing all 176 people aboard, despite days of denials by the Islamic Republic.