Triangle craft with green lights gliding through sky

I am a police officer and deputy sheriff. While on duty after dark, near the top of my windshield (frame of view) I witnessed movement in the sky (southbound direction of view). Upon concentrating my focus, viewing through the low light, I was able to make out a triangle craft, with 3 dim green lights per side (just bright enough to assess size, shape, and movement). The craft moved to my right (westbound). Due to tree coverage, I lost sight of it quickly, to which I never located it again, maintaining visual contact for less than 10 seconds. While it appeared very low, it is difficult to determine distance, size, and speed, given the relationship between those factors. I did not hear any noises, however I was at speed on the roadway inside a vehicle.
I am privy to what helicopters and airplanes look like in the sky, frequently working alongside medical flight crews in the area, and where nearby airports are, making me somewhat familiar with common areas of the sky in which low air travel is common. This was unlike anything I had ever witnessed.
It should also be noted, that within approximately one hour of my sighting, I responded to a call from a homeowner reporting hearing something running outside of his home, to which he stated did not sound like an animal. The callers’ residence was in the direction from which the object came when I witnessed it, as the crow flies, in a heavily wooded and forested area. There were no other similar or relevant calls, and no reported sightings through our 911 center.