Several lights over Roseville, California

On January 14, 2015, in Roseville (California), a man took photos of a pretty sunset. Later, he noticed several lights arranged in a circle. These UFO (or this?) was not visible to naked eye.

Witness statement:

I was taking a picture of the evening sky. I was going to send the photo to my girlfriend and saw the circle of lights in the picture. I was taken using an iPhone5s. I have three other photos that were taken back to back and only one contained the lights. I still can't believe myself!