Intriguingly, they went on to reveal that their phone began experiencing technical issues moments after they filmed the weird UFO over the city, leading to speculation that some kind of ‘alien interference’ was to blame.

As for what the object could have been, setting aside the extraterrestrial hypothesis, some have suggested that the oddity could be a drone or a similar remote controlled vehicle, while others have posited that it might have simply been an errant balloon. What do you think was filmed over Karlsruhe on Sunday evening? Share your best guess with us at the C2C Facebook page.