Iranian Minister of Road and Transportation Hamid Behbahani said on Monday that bad weather and the pilot's lack of enough vision were causes of plane crash in northwestern part of the country, ISNA reported.
Behbahani confirmed no inferno occurred following the deadly incident and said, "so far 78 people were killed and some 24 were injured."
Also the Head of crisis management organization of Iranian Ministry of Road and Transportation Ahmad Majidi told ISNA that, the plane's black box has not been found yet.
Boeing 727 planes have been operating in Iran for over three years and were delivered to the country in 1974 as used planes.
Majidi said, "105 people including 94 passengers and 11 crew members were on board at the time of the accident."
The aircraft was heading from capital Tehran to northwestern city of Orumiyeh.
"26 wounded individuals are hospitalized in Orumiyeh, one of them in critical condition," Majidi said adding an individual has gone missing following the plane crash.
Iranian Deputy Minister of Road and Transportation confirmed the plane was wrecked and said, "the pilot intended to return to Tehran after bad weather had made it impossible for him to land."
He also said, "pilot was dead after the crash."
The pilot reported to lack enough vision to land at the airport was made to bring down the plane in farmland where the accident occurred.
The dead include 12 women and 42 men, but the identities of other 23 people have not been found yet.
Reports say the injured include18 men and 9 women, but 3 crew members are alive.
The Boeing 727 which operated by Iran's national airline crashed at 19:45 pm local time on Sunday.