UFO over Germany Above top secret

I was having an evening meal with friends (Cologne, Germany) at the 10th of May this year. Suddenly my sister noticed an object flying over us at a huge speed (to fast for a balloon) and emiting no sound. The object flew in a straight line past us. After that object had passed, another object followed it. This happened until about 7 objects had passed us. Then, all of the objects met together and therefore decreased speed. Suddenly, all of them flew out of sight due to a sudden burst of high acceleration.
Luckily, a friend was able to shoot some pictures. Author Peter Klein