An Iranian commercial plane crashed in a mountainous region of southern Iran on Sunday morning, killing all 66 people on board, a tragic consequences of Iran's rapidly aging fleet of commercial aircraft according to the Associated Press.

The plane was an Aseman Airlines ATR-72, a twin-engine turboprop used for short-distance regional flying. It went down near its destination of the southern Iranian city of Yasuj, some 780 kilometers (485 miles) south of the Iranian capital, Tehran.

Aseman Airlines spokesman Mohammad Taghi Tabatabai told state TV that all passengers and crew aboard Flight No. EP3704 were killed in the crash.

"After searching the area, we learned that unfortunately ... our dear passengers had lost their lives," Tabatabai said. "This plane had 60 passengers, 59 adults and one child, as well as a pilot, a co-pilot, two flight attendants and two air marshals on board."

Heavy fog prevented rescue helicopters from reaching the crash site in the Zagros Mountains, state TV reported. Tabatabai said the plane crashed into Mount Dena, which is about 4,400 meters (14,435 feet) tall.

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— خبرگزاری تسنیم