Thick fog and limited daylight is hampering efforts to find Iran's president, Ebrahim Raisi and other officials.

The convoy of three helicopters was on its way back to Tehran, and one was forced to make a "hard landing" due to the bad weather and fog near the border with Azerbaijan.

US Correspondent Richard Arnold told Mike Hosking “They still haven't found the crash site.” 

Arnold said “Raisi is known as the ‘Butcher of Tehran’, he brought in the execution of thousands of political dissidents in the late 80s.” 

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