Stars moving in a straight line.

I know this was a while ago, but I will describe this the best I can. I used to live in Darby,Montana about 7 years ago. One night while a friend, and myself sat around a camp fire, I saw something different than I have ever seen before. I am not sure exactly what it was. I was looking up at the night sky, and saw what looked like stars moving. These objects seemed to be pretty high up in the sky, so I really could not give details about what shape they were, etc. They just looked like stars moving very fast. They were all moving in pretty much a straight line at first. I watched these things moving, and told my friend to look. We were both kind of wondering what this could be because we had never seen such a thing before. The objects appeared to be fluttering, kind of shaking rapidly as they moved. I grabbed a flashlight, and beamed them, and then one branched off. The others went on in the same straight line. I kept my eyes on the one that branched off, and after a minute or two lost it behind a tree. My friend, who is the toughest guy I know went inside with his eyes wattering! I just wanted to share this with you because it was pretty unusual.I remember at first thinking these might be satellites, but I am not sure that a satellite can flutter, and make a ninety degree turn in the sky! I wonder if anyone else has had similar experiences. What I saw was not to spectacular, but pretty unusual. Not sure of exact date and time.
Date is approximate.  PD