Mysterious noises coming from Apple Sunnyvale complex

SUNNYVALE, Calif. (KGO) -- A mysterious noise is coming from an Apple complex in Sunnyvale. It sounds like some type of industrial machine ramping up, but Apple will not confirm what it is.

Security is tight around the complex. Everyone is making a guess as to what exactly Apple may be doing in the overnight hours. They have been secretly working on something and neighbors are guessing it's a car. The San Jose Mercury News reports Apple received permits that describe their buildings to be an auto work area and a repair garage. Now the speculation is Apple could be working on a self-driving or an electric car.

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Another explanation why the work is going on at night, according to the Mercury, off-peak electricity is cheaper especially during massive power consumption.

Apple's spokesperson will not confirm or deny that they are building a high tech car, but they did say Apple has "a long history of developing auto related products."

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