A missile test off the California coast sparked a frenzy on social media and spooked residents who believed they had just seen a UFO.

The Twitter hashtags #Navy, #comet and #UFO were trending as social media users uploaded videos and pictures of the mysterious bright light illuminating the night skies.

The San Diego Union-Tribune said that the streaking light was visible as far away as Nevada and Arizona and authorities were reportedly flooded with calls. 

But just when some were predicting the end of the world, officials moved to clear up the mystery.

The Orange County sheriff said the light was from a naval test fire made off the California coastline.

Aviation officials had warned of possible US military activity.