Very strange shape caught over Garden Grove, CA

On July 27, 2017, a witness saw a oddly UFO flying in the blue sky over Garden Grove, California, USA.

Eyewitness statement:

Driving east stopping at a stop sign and caught a glimmer of something approximately 500 ft out of my driver side window. There is an airport in the area but this wasn't a plane. At first thought it could be balloons but after stopping someone, they were as stunned as I was. I took several photo's all the way back to my house. It changed shape and hovered in one spot. Not a helicopter either.