Round, shiny objects flying in formation moved in ways not consistent with aircraft, balloons or anything elseI was in an industrial area of a large Southern city that boarders a very large military base. Around 14:30 I was standing in a large lot looking up at the completely clear sky. Almost immediately I saw two groups of 4 each objects approximately 500-700 feet in the sky moving in two formations of 4 each on "Y" shadows with the bottom of the "Y" being the lead in each group. The objects were very shiny and each had a prominent white, thick, round, white circle within each object. Both groups were moving East to West. At first, I thought they might be balloons, mini-helicopters or drones. But each group would move in formation and then suddenly completely stop, then shoot up, down, backwards and then race forward at amazingly speed. Then at one point, both groups shot up until they could no longer be seen. During these "maneuvers " several times one object in each formation would break away