Big Bear City, CA — Residents in the East Valley may have felt a strong rattle for a few seconds last night, at about 9:30pm, which was preceded by a rumbling that sounded like an earthquake coming on. However, the ground did not shake, and there are no reports of earthquakes at that time posted by the U.S. Geological Survey. Local emergency agencies are also unsure of what the cause of this sonic boom type sound may have been, though likely a military jet flyby, again, Monday, March 29 around 9:30pm.