At 2:40 p.m., a caller reported seeing a piece of silver metal fall from the sky over Interstate 8 by the Pine Valley bridge, according to a California Highway Patrol dispatcher.
A second caller reported seeing something on fire fall from the sky, said Lt. Anthony Ray of the San Diego Sheriff's Department.
Cal Fire sent an air tanker to check out the reports and a San Diego Sheriff's Department helicopter crew also looked for the unidentified falling object, Ray said.
Officers checked with Lindbergh Field and said no planes had been reported missing, according to Ray.
The search continued for more than an hour after the first call, but deputies on the ground and in the air had not found anything, Ray said.