An Atlasjet plane crashed shortly before it was to land in central Turkey early Friday, killing all 56 people on board, the airline's chief executive said. A rescue helicopter had reached the wreckage of the plane on a mountainous region near the town of Keciborlu, in Isparta province, and reported back that no one had survived the crash, airline CEO Tuncay Doganer said.

Doganer said the cause of the crash was not known. But he ruled out weather conditions as a possible cause, saying there was no fog or strong winds at the time of the crash. The MD-83 jetliner with 49 passengers and seven crew members took off from Istanbul around 1 a.m., headed to Isparta, but went off the radar just before landing at the airport near the city of Isparta.

Helicopters took off from Ankara, the capital, to search for the plane. It was spotted some five hours after it went missing. "There was no abnormal situation where weather conditions or the plane's technical condition are concerned," Transport Minister Binali Yildirim said. The private airline, established in 2001, operates regular flights inside Turkey and chartered flights to Europe and other foreign destinations.