Metallic oval-shaped UFO caught over Berlin, Germany

On April 24, 2015, a security camera located in Berlin (Germany) has filmed a weird and metallic oval-shaped UFO moving quickly in the sky. A woman has noticed it and she takes a screenshot.

Witness statement:

On Potsdamer Platz (Berlin-Germany) there's a high tower on which they have a web cam. I was checking what the view looks like from there as I was planning to take my parents to the tower. The webcam takes a picture every minute or so I guess. When I checked it, I saw an unusual object (metal aspect/egg shape) that seemed to be in movement. The image I saw on screen was still though. I screenshot it, that's how I know the exact moment it happened (because the file of this picture is named after date and time). At the next picture taken by the webcam, the object was gone.
I attach the screenshot I took below.
Thank you for all the work you do! I'm really looking forward to hear what you think this object could be.
Kind regards,