I filmed these last night at around midnight

I saw these lights moving across the sky last night as I was going to bed. When I first saw them there were 3 lights, one further ahead, and two following it, kinda intertwining with each other. once I began filming, one of the two in the back blinked and disappeared leaving just two in sight (seen in this clip). Then about 5 minutes later, a 4th light made the same trip but disappeared once it got past last tall building in the video. They were all red, not blinking, and whenever we see drones or helicopters we can hear them from the flat as sound travels well from how high up we are. Any ideas what they are? I have another video but could only upload one at a time