The helicopter was carrying Iranian president Ebrahim Raisi and Iranian Minister of Foreign Affairs Hossein Amir-Abdollahian
It is said to have "hard landing" near Varzeghan in the East Azerbaijan region of Iran.
Rescue teams are searching for the aircraft. Latest reports say the chopper has been found.
Iranian officials say weather conditions in the crash area are becoming more difficult, heavy rain is turning to snow.
Keep your eyes on opening oil prices, this should give it a bit of a wobble if nothing else.
In Tehran, a significant deployment of Iranian Security and Military Personnel has been reported.
