UFO Sighting [Representational Image]
UFO Sighting [Representational Image]YouTube

Mysterious hole in the cloud have been reportedly seen over Stockton, Northern California on Friday, 9 May 2014. Photos of the strange objects grabbed worldwide speculation with people wondering as to what must have caused the phenomenon, reported Daily Mail.

Many speculated that the strange cloud can be an Unidentified Flying Object (UFO) or an extraterrestrial life form.

Many people flocked on Facebook, Twitter and Instagram to share their thoughts and photos on what appeared to be a strange, bright hole in the undisturbed clouds over the city.

National Oceanic and Atmospheric Administration (NOAA) has suggested that the weird phenomenon is caused by "hole punch cloud," according to News10ABC.

A hole punch cloud is formed when the temperature in the white cloud drops below the freezing point and forms ice crystals. The evaporating crystals leave behind a hole in the cloud. The phenomenon is scientifically termed as "Fallstreak hole," explained NOAA.

A similar event was reported in Northern California back in 2010, which captured global attention. Though these types of formations are common in different parts of the world, experts disagree to this theory considering the fact that Stockton is comparatively warmer this year.

To look at the pictures of the mysterious hole in the cloud, check here.

In another UFO sighting, crew from Australia's TV production captured two UFO hovering over Queenstown, New Zealand. The sighting was captured while shooting for the seventh season of "Colour In Your Life" series.

The video of the UFO uploaded by the TV programme, captured international speculation from social media portals. The sightings were captured on 3 May 2014, while filming for the first episode of the series. But it was only when the crew started reviewing the edited footage, they noticed two mysterious objects flying.