Black flying saucer photographed in Orange County

On October 3, 2014, an automobilist drove between the cities of Irvine and Tustin (in California). Suddenly, he has noticed, high in the sky, a possible dark flying saucer. Witness has sighted this UFO during several minutes. What is it?

Witness statement:

I was driving north from Woodbury area to Paseo Westpark area. I first noticed a black disk like object hovering over what seemed like Tustin District area. It didn't move, or have any lights. Then I noticed 2 black/dark helicopters flying away from the object. As I turned on Irvine Center Drive towards Culver, I saw the object directly in front of me. The object seemed to be hovering for at least 6 minutes or so. Then as I got closer, it seemed to have moved at a rapid speed towards north. I then followed it to Tustin Ranch Road where it was about 300 feet from the ground flying almost parallel to Tustin Ranch Road right by the 2 large hangers. Once I reached Walnut, the object flew NE in tremendous speed. At this point, I could not even see it in the sky as it had flew super fast, very far away. I thought at this point it must have been an airplane. I turned around to head back to Paseo Westpark, when I looked in my rear view mirror and saw the object was back hovering over the District area. This could not be an airplane as it hovered for long periods of time, flew with great speed, THEN somehow turned around and came back to the same spot within a couple minutes. I again made a U turn to follow the object when it just disappeared. At this point, the sun was setting and got very dark so I couldn't see it even if it was up in the sky. I'd like to add that there were several commercial planes flying into SNA that must have seen this object.