As I was walking my dog at approximately 12:00 noon, on a beautiful clear day, I saw what I first thought were a group of birds high in the sky.

After watching for a few moments, I noticed that this cluster of round objects were stationary.  They were silent and grouped together hovering.  They were white and seemed to have light within them.  
They began to move across the sky very slowly.  At times they seemed to vanished but would reappear seconds later.  
I also noticed another object that looked more cylinder shaped, moving near the cluster of objects. 
When the objects would fade away for a few seconds, the cylinder shaped object would still remain.  They slowly moved across the sky until I no longer could see them.  This lasted for approximately 10 minutes.  Not long after the objects left, a small airplane was circling the area.  
Not sure what I witnessed, but very interesting.
Witness elects to remain totally anonymous; provides no contact information.  PD