Early Wednesday, a day after the Russian-made Tu-154 Tupolev airliner crashed in bad weather, 15 search parties headed up into the snow and fog that covered the bitterly cold reaches of the Sefid Kouh mountain.
All aboard the plane were presumed dead.
Iranian radio and television reported that the airliner, operated by state-owned Iran Air Tours, crashed early Tuesday outside Khorramabad, about 230 miles southwest of the Iranian capital, Tehran.
Rescuers on a single helicopter that took off during a brief morning lull in the heavy snow and rain spotted more than 40 bodies on the ground, but the team could not land and was forced to return to its base when the weather turned bad, a search operation leader and state-run radio reported.
Overnight, bulldozers cut a path from the nearest village to the foot of the mountain, where the army, paramilitary Revolutionary Guards and the Red Crescent set up an operating base with more than a dozen tents.
About a dozen relatives of the plane victims gathered at the base, 15 miles west of Khorramabad, the provincial capital of Lorestan.
Shapour Parnian, dressed in black, cried for his brother, Bahman Parnian, a senior Transportation Ministry official.
"I want my brother back. What a calamity this is for us today," he said.
The search was halted Tuesday night because of nightfall and bad weather.
Behrouz Goudarzy, deputy governor general of Lorestan province, told state television that helicopters are being brought to the area because the rocky terrain makes it difficult to reach the crash site by land.
However, the weather rendered them useless Wednesday and was expected to continue for several days.
Since Tuesday, at least three of the rescuers returned to the base with broken bones, said police Col. Mohammad Paziresh.
Lorestan's governor general, Nourollah Abedi, declared three days of mourning in the province.
The state-owned Iran newspaper said those on board included 105 passengers and 12 crew members, instead of 13 crew reported Tuesday by government spokesman Abdullah Ramezanzadeh. Four Spaniards who worked for Spanish electronics manufacturer Fagor were aboard the flight the paper said.
According to Goudarzy, at least 10 government officials also were aboard.
All those aboard were believed dead, Reza Niknam, an adviser to the governor general of Lorestan province, said Tuesday night.
The plane lost contact with the control tower at Khorramabad airport minutes before crashing into the Sefid Kouh mountains, or white mountains in the Persian language.
The cause of the crash of Flight 956 was not known, but officials said the aircraft went down in bad weather.
"I heard a huge, really horrifying sound of an explosion," said Ardeshir Ghiyasvand, 34, f Key-Mirzavand village. "Moments later, I saw that the clouds and fog over the mountains suddenly became red, everything turned from white to red. It remained like that for a few seconds."
Hamid Fouladvand, another official who managed to reach the crash site more than 230 miles southwest of Tehran, said he saw "dozens of bodies scattered deep in the valley."
"I also saw pieces of the plane. Wolves and bears were in the area and if the bodies aren't collected soon, they will be eaten," he said.
Army commanders ordered fires to be lit around the site overnight and troops fired shots into the air to frighten away the animals.
In Moscow, Tupolev chief designer Aleksandr Shingart told Ekho Moskvy radio that the plane received a "proper" routine servicing in January. "It was immaculate and was thoroughly checked," he said.
He suggested pilot error might be to blame.
Iranian television reported that President Mohammad Khatami ordered an emergency committee to investigate, and that Transportation Ministry experts were dispatched.
Nasrin Shafiiyan, whose husband Houshang was on the plane, said the crash was the fault of "the stupid incompetent officials who go and collect secondhand ... planes from all over the former Soviet countries. What is this garbage they buy or rent?"
Iranian airlines have been accident-prone in recent years. U.S. sanctions make it difficult for them to buy spare parts for their elderly Boeing aircraft, mostly bought before the 1979 Islamic Revolution.
They have turned instead to former Soviet countries from which they lease aircraft.
The maker of the crashed plane, a Tupolev, said the aircraft was in first-class condition, but Iranian media were quick to apportion blame.
"Again another old Russian plane crashed," declared the daily Siyasat-e Rouz in a banner headline.
Parliamentarians have called for the resignation of Transport Minister Ahmad Khorram and aviation agency head Behzad Mazaheri.
Khorram rejected accusations of lax flight safety in a heated exchange in parliament and said the public was "too sensitive" to the issue.
"Each year, 17,000 people are killed in road accidents and the press does not pay much attention to it, but they have paid so much attention to two plane crashes this year which caused the deaths of 150 people," the official IRNA news agency quoted him as saying.
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