I saw a Flashing light in a height about 5 Km.it was going around a circle and flashing very fast.the color was turning red to blue.I saw a strange flashing light with a color turning Red to blue.it was flashing very faster than a Plane or Helicopter.at the first time It seems to be stable in the air but after watching carefully I awared that was going around on surrounding a little circle. That unknown objects was flying in a height about 5000 meters above the ground and it leaved to the north and disappeared.