ALMATY (Reuters) - A military transport plane crashed in southern Kazakhstan on Tuesday, killing all 27 people on board, including the commander of the Central Asian nation's border guards, local media and the KNB security service said. The twin-engine Antonov An-72 jet disappeared from radar screens at about 1900 local time (1300 GMT) as it was making a descent near the city of Shymkent, the capital of the South Kazakhstan Region. Kazakhstan's Channel 7 television showed early footage of charred and mangled fragments of the airplane scattered around a cordoned off area in a raging blizzard. The passengers also included senior border guard officers from southern Kazakhstan. The border guards had been due to make a stopover in Shymkent and then fly to the Uzbek capital Tashkent for talks with Uzbek colleagues, local media said. The plane plunged to the ground in bad weather from an altitude of about 800 meters as it was making a fourth circle, trying to land, Kazakh television channels said. KTK channel broadcast footage of an eyewitness saying he had heard a loud explosion and had seen flames at the crash site. Quoting Kazakh air traffic controllers, Channel 7 said the plane had crashed into an open-cast mine some 21 km (13 miles) from Shymkent, and rescue teams could not immediately reach the crash site. Reporting by Dmitry Solovyov; Additional reporting by Mariya Gordeyeva; Editing by Myra MacDonald