Turkish and Spanish experts struggled Tuesday to identify the charred remains of 75 people, mostly Spanish peacekeepers returning from Afghanistan, killed when their plane crashed into a remote Turkish mountain.

Turkey's military had retrieved all the bodies from the crash site, some 470 miles northeast of the Turkish capital, Ankara (search), and was just beginning the difficult task of identifying the severely burned bodies.

A private television channel said only a fraction of the bodies had been identified and that DNA (searchtesting would be required.

The plane was flying from Kabul, Afghanistan, to Zaragoza, Spain, with a refueling stop in the Black Sea port city of Trabzon when it crashed.

The Russian-made YAK-42D went in to land, but was flying too high, and turned toward nearby fog-shrouded mountains, officials said. The plane crashed on a mountain slope and exploded in flames.

Spain's Defense Minister Federico Trillo (search), was in Trabzon to help with investigations and coordinate the repatriation of the bodies. He was accompanied by a Spanish medical team that was working to help identify the remains kept at a refrigerated storehouse.

The airplane, which belonged to Ukrainian-Mediterranean Airlines, carried 62 Spanish peacekeepers, 12 Ukrainian crew members and a Belarusian flight manager. All were killed.

The cause of the pre-dawn accident was not clear. Trillo said bad weather -- fog and strong wind -- appeared to be to blame, but radio contact with the plane was cut off just before the crash, and Turkish aviation officials speculated there may have been a technical malfunction.

Soldiers have not yet located the flight recorder.

The Spanish peacekeepers had just finished a four-month tour of duty. They were reportedly the first deaths among Spanish troops in the 17 months they have been involved in the Afghan peacekeeping mission.

Some 5,000 peacekeepers patrol the Afghan capital of Kabul under join German and Dutch command, including 141 soldiers from Spain. Most of the Spaniards are engineers who work in construction and explosive ordnance disposal.

There are also some 8,500 U.S. forces in Afghanistan, who are hunting down Taliban and Al Qaeda remnants.