Black triangular UFO seen over a small town in the Netherlands

On May 21, 2018, a witness was smoking a cigarette in his garden when he saw a triangular UFO over the town of Nieuwerkerk aan den Ijssel, in the western Netherlands.

Witness statement:

When smoking a cigarette in my garden I noticed a bright white flash in the sky near the star Arcturus. (I hope it's the correct star. I had to look it up. After drawing a straight line in my mind from the end of the handle of the Big Dipper.) I don't know if this event is related to my sighting, but when I looked in the direction of the star to see if another flash would appear I suddenly noticed a very big triangular shapeded flying object traveling at high speed across the sky. It looked to be flying quit low. Lower than commercial airliners. More at a hight of a small passenger plane or helicopter. The triangle was black with orange-red lights at each corner at the bottom. The lights were not very bright and the shape of the object was faintly visible. The object did block the light of the starts above. The triangle was traveling in a straight line from North to South at approximately 00:30 PM (CET) on May 21th, 2018 over Nieuwerkerk aan den IJssel in The Netherlands. After seeing it for a few seconds it disappeared from sight behind some houses.

I never seen anything like the traingle shaped object ever before. It's not something I know off or which in my opinion could be technologically possible at this moment. That shape, that big en that fast whitout any sound? I was really stardeled. I've seen television programs about UFO's and always thought: "It'll probably be something that can be explained rationally." or "I think this person isn't quit sane." After this experience I can only say: "There really are unidentified flying objects in the sky." I still can't understand what I just witnessed. Was it alien or some top secret highly advanced technological aircraft? At this moment I don't know what is more likely.

Source, 20th May 2018