Based on the latest data, the asteroid was 10 feet (3 meters) in diameter with a mass of a few tons and a kinetic energy of approximately half a kiloton - entered Earth's atmosphere above Arizona just before 4 a.m. local (MST) time. NASA estimates that the asteroid was moving at about 40,200 miles per hour (64,700 kilometers per hour).
Bill Cooke in NASA's Meteoroid Environment Office notes that this is the brightest fireball detected in the 8-year history of the NASA's All Sky Fireball Network and that he and other meteor experts are having difficulty obtaining data on the June 2, 2016 fireball from meteor camera videos, since many of the cameras were almost completely saturated by the bright event.
“There are no reports of any damage or injuries but there are almost certainly meteorites scattered on the ground north of Tucson" said the NASA analyst.
Eyewitness reports placed the object at an altitude of 57 miles above the Tonto National Forest east of the town of Payson, moving almost due south. It was last seen at an altitude of 22 miles above that same forest.
If you take a look at the AMS-NASA data of the number of fireballs in USA registered since 2005, you see an increasing number of fireballs. Comparing the number of fireballs in 2005 with 2015 onwards, it shows that the threat to earth from asteroids and comets increases year by year.
The next footage below is from the Sedona Red Rock Cam (part of the EarthCam network) shows how brightly the ground was illuminated during the fireball, which entered the atmosphere over Arizona shortly before 4 a.m. MST on June 2, 2016.