Evidence suggests an Iranian missile brought down a Ukrainian passenger plane that crashed near Tehran, possibly in error, Western leaders say.
Canada and the UK called for a full and thorough investigation into the crash, which killed all 176 people on board.
Iran’s civil aviation chief, however, said he was “certain” that the plane was not hit by a missile.
The crash came just hours after Iran carried out missile strikes on two airbases housing US forces in Iraq.
US media have speculated that the timing of the crash suggests the plane may have been mistaken for a US warplane as Iran prepared for possible US retaliation for the strikes.
Victims included 82 Iranians, 63 Canadians and 11 Ukrainians as well as nationals from Sweden, the UK, Afghanistan and Germany.
CBS News quoted US intelligence sources as saying a satellite detected infrared “blips” of two missile launches, followed by another blip of an explosion.