Four red lights near Aarhus, Denmark

The clip shows a twilight sky above a residential area near Aarhus, Denmark. The poster says they saw four red lights, one of them flashing, and heard a propeller-like noise. They report that three lights stayed nearly motionless while the leading light moved farther away.

The clip does not establish what the lights were. A flashing light and propeller noise could fit an aircraft or drone, but the observation alone does not confirm their source.