Ukraine's President Leonid Kuchma has ordered an inquiry into the crash of a Ukrainian airliner in Turkey which killed all 75 people on board, most of them Spanish peacekeepers.
The airliner was said to be in good working order
The chartered Yak-42 plane hit a mountain near the Black Sea resort of Trabzon after the pilot tried to land in thick fog and heavy winds in order to refuel early on Monday.
Sixty-two Spanish peacekeepers returning home from Afghanistan and 13 crew members - reportedly 12 Ukrainians and one Russian - were killed.
The Spanish defence ministry said in a statement that according to initial indications the cause of the crash "was the dense fog in the area".
There were flames everywhere. I couldn't get close to it for 15 to 20 minutes
Earlier, officials from the aircraft's Ukrainian owners, Mediterranean Airlines, said the 15-year-old plane had been well maintained and fully modernised in 2001.
"The plane was in good technical condition and the crew were well prepared," the company's deputy general director Volodymyr Gorbanovsky was quoted as saying by Reuters news agency.
The commander of the peacekeeping International Security Assistance Force (Isaf) in Afghanistan, Brigadier-General Robert Bertholee, said his soldiers were "deeply shocked" by the tragedy.
The governments in Afghanistan and Ukraine have sent condolences to the families of the dead.
The plane - which is believed to have been carrying some ammunition - was flying from the Kyrgyz city of Bishkek to Zaragoza in Spain after leaving Kabul on Sunday.
It had been due to make a refuelling stop in Trabzon, but hit a mountain slope 50 kilometres (30 miles) south of the town according to local media reports.
First developed by Yakovlev Design Bureau, Russia
Entered service: 1980
Aircraft length: 36.38m
Cruising speed: 800+ km/h
Passengers: Up to 120
Television pictures from the scene show smoking wreckage scattered across the misty hillside.
Correspondents say that - judging by the crash site - those on board stood no chance of survival.
Trabzon Governor Aslan Yildirim told CNN-Turk television that Turkish soldiers had retrieved more than 25 bodies from the wreckage.
Local officials said that the plane crashed during its third attempt to land in thick fog.
The pilot had said that he was unable to see the runway - visibility was less than 10 metres - the plane then disappeared from radar screens.
Spain's Defence Minister Federico Trillo will travel to Turkey on Monday to organise the repatriation of the soldiers. He is travelling with army investigators and doctors.
Spain's defence ministry said the peacekeepers were returning from a four-month mission in Afghanistan.
The Spanish defence ministry hired the airliner from Mediterranean Airways which runs charter flights for Egypt, Greece, Italy, Lebanon, Spain and Turkey.
When the plane refuelled at Kyrgyzstan's Manas airport and left some of its cargo there, it was reported to be in good working order.
Turkish military troops and ambulances immediately rushed to the scene of the crash, near the town of Macka, to rescue possible survivors, the Anatolia
news agency said.
One witness said the wreckage of the plane was in flames and reported seeing at least two charred bodies, private Kanal 7 television reported.
"There were flames everywhere. I couldn't get close to it for 15 to 20 minutes," Sait Topcu, a cleric at a mosque in a nearby village, was quoted as saying.
Spain has contributed 120 peacekeepers to the Isaf, which is responsible for helping to maintain security in the Afghan capital.
The crash is the third of a Ukrainian-operated jet in the past six months.
On 9 May, around 160 people died when the cargo-bay door on an Ilyushin-76 transport aircraft run by Ukraine's defence ministry and piloted by a Ukrainian crew flew open over the Democratic Republic of Congo.
In December, 44 people, mainly Ukrainians, died when a Ukrainian-made Antonov An-140 crashed in Iran.
Correspondents say Ukrainian charter companies have become major players in international military and commercial missions over the last 10 years.
They offer lower rates and cheaper crews in the fiercely competitive market.
But some experts have blamed the lack of safety regulations, chronic underfunding and also using ageing aircraft for the grim safety record of Ukraine's air charter industry.