2 Parades of satellites, 40 total, west to east across Las Vegas sky

Out walking dog in darkness, looked up to see what appeared to ba a satellite traveling west to east, but then noticed another following in it's same path about 5 arc seconds behind, then looked west to see another and another ( all coming out of a small cloud formation floating by.  There were 2 that were "out of this singular formation" as if slowly passing the object in front of it.  I ran into house to grab my Celestron Binocs to see if I could detect a shape - I could not as if they were too high up, too small, or in orbit... however they were all very bright, slightly less than Sirius.  After what appeared to be the last one, I continued to watch the sky and about 1 minute later, another series of these objects started to come over, about the same distance in between, but slightly faster. The path of these new objects were also west to east but slightly farther south in the sky. There was about 8 to 10 in total, in this second grouping, then a g! ap of maybe 30 seconds and then a very bright object, traveling much faster seemed to be trying to catch up. All these objects were now fading into the gathering light of dawn in the eastern sky. I tried to photograph these objects with my cell phone but it was inadequate to catch more than just a few seconds of one object. The dark sky was very still with no other objects noticed while viewing the above mentioned ones.