Many people find it hard to trust alleged UFO sightings as much as they want to believe. Photographic evidence of UFO sightings is usually too small and grainy. Clear images are often debunked as hoaxes too.

However, the following story features somewhat believable images. These images may not depict UFOs very well, but the truth may be even more unusual than many would think.

In 1971, an American Navy submarine USS Trepang was on a voyage in the Arctic Ocean to test its weapons under the ice caps.

An anonymous source claims that Klika saw a strange object flying overhead while looking through the periscope. What he did see would be 40 years before it was answered.

The French publication Top Secret printed images in an article in 2015 claiming that an unnamed source provided the photograph.

Beyond the photos, only a little information was provided, but some were officially marked “not to be released” and “Unauthorized Disclosure Subject.” Despite the markings that seem to be warnings, the publication printed 11 pictures; each one shows an apparent massive object hovering above and possibly crashing into the water.

The article of the images says that they are showing a triangular-shaped UFO without a doubt.