Set of three bright white lights moving in formation

I was standing on my balcony facing east. I saw three bright white lights in a northeast direction, to my left, low to the horizon. At first I thought they were stationary, so I assumed they were stars, maybe Orion’s Belt. But after staring at them for a minute, I realized they were moving, almost imperceptibly at first. Then they got brighter, brighter than any star, and they were going lower in the horizon moving to the right and moving faster (losing altitude going south I think). They never broke a linear left to right formation. It was dark so I could not see any structure and the lights were so bright. It could have been three different structures, or three points of light on a single structure. They moved low enough to become blocked by nearby housing. After that, I could not see them again.