Detecting strange footprints near the ocean surface nearly 4km

70% of the Earth's surface is hidden beneath the ocean, but 95% of the ocean is still unexplored by humans.

Strange footprints were found in the ocean floor by a deep-diving robot belonging to a British study of the National Oceanographic Center in Southampton.

These traces are too large to be created by fish or any creature living in the sea.

Scientists have ruled out these mysterious traces as a result of mining or scientific activities. These tracks, measuring 1.98m long and 33cm deep, were detected 2.4 miles (about 3.86 km) from the surface of the Pacific Ocean, in the middle of Mexico and Hawaii.

They also said that these traces are too large to be created by any fish or any other creature that lives in the deep sea.

The study's lead author, Dr. Leigh Marsh, told Express: 'According to the analysis, these dents are not randomly distributed' . She added that it is very likely that the owner of these traces is 'deep dolphins'.

Although whales often do not dive too deeply, similar traces found throughout the world suggest that this large mammal can randomly fall to a depth of 2.5 miles and even more.

Scientists believe that 'depth-measuring electronic tags, attached to these animals, will provide direct evidence that whales can dive to unrecognizable worms like this.' .

While discovering the mysterious footprints at the bottom of the ocean confuses researchers, those who believe in "conspiracy theory" quickly assert that UFO technology has created these traces.