Iran's military has announced that it "unintentionally" shot down a Ukrainian passenger jet.
A statement overnight blames "human error" for Wednesday's crash, which killed all 176 people on board.
It came hours after Tehran launched missiles at US military bases, following the killing of the country's top general.
Mostly Iranians and Canadians were killed in the plane crash, with Canadian prime minister Justin Trudeau reacting by saying: "Our focus remains closure, accountability, transparency, and justice for the families and loved ones of the victims. This is a national tragedy, and all Canadians are mourning together.
A military statement carried by Iranian state media said the plane had flown close to a "sensitive military centre" and was mistaken for a "hostile target".
It said the people responsible would be held accountable and expressed condolences to the victims' families.