A plane has crashed in southern Iran with 66 people on board, according to a spokesman for Aseman Airlines.
The 24-year-old ATR-72, a twin-engine turboprop, left the Iranian capital Tehran at around 8am local time and crashed about an hour later.
The plane went down near the remote mountain town of Semirom, about 390 miles south of Tehran.
It had been heading to the southern city of Yasuj, in Isfahan province.
Aseman Airlines spokesman Mohammad Taghi Tabatabai said there had been 60 passengers on board, including one child, and six crew.
He added: After searches in the area, unfortunately we were informed that the plane crashed.
“Unfortunately, all our dear ones lost their lives in this incident.
Later, however, he reportedly told ISNA news agency: Given the special circumstances of the region, we still have no access to the spot of the crash and therefore we cannot accurately and definitely confirm the death of all passengers of this plane.
The plane is thought to have crashed into Mount Dena, a sub-range of the Zagros Mountains.
According to Mehr News Agency, it appeared to have been attempting an emergency landing.
State TV said nobody had yet managed to reach the scene.
Fog is preventing helicopters from getting there and Iran’s Red Crescent has deployed workers on foot.
Aseman is a semi-private airline that specialises in flights to remote airfields in Iran and also flies to some international destinations.
The carrier, Iran’s third largest, has 29 planes, including six ATR-72 aircraft, according to plane-tracking website FlightRadar24.
Iran’s commercial air fleet has suffered during decades of international sanctions that have made it difficult to buy newer aircraft, with planes being involved in a number of accidents.
After the landmark 2015 nuclear agreement loosened the restrictions, the country signed deals to buy dozens of new passenger planes, including a $536m (£382m) deal with ATR last April for at least 20 aircraft.