[Photo] Greenland shark, Somniosus microcephalus. Killer with a smile: The Greenland shark might look friendly but the beast is known to attack polar bears

A daredevil photographer went to extraordinary lengths to photograph these rarely seen sharks, which look like they have been etched from stone.

These incredible Greenland sharks can survive for more than 200 years at depths of up to 600 metres under Arctic ice.

Bigger than the notorious great white, they grow to 23-feet long and are so fearsome they have even been known to eat polar bears.

They live further north than any other shark species and can swim in waters where temperatures plummet to just one degree celsius.

Doug Perrine had a close encounter with the elusive creatures when they ventured into the warmer waters of the St Lawrence River in North America, hunting for food.

The sharks usually eat large seals but have even been known to polish off polar bears and reindeer.

But 59-year-old Mr Perrine, from Kailua Kona, Hawaii, was brave enough to swim to just a metre away from the giants to get his shots.

He said: 'These sharks were very placid and curious. They are much calmer than other sharks - they have an almost goofy, comical appearance.

'I was amazed because most sharks are very shy of divers and tend to avoid the sound of scuba bubbles, but these these were attracted to the sound. They even swam closer to investigate.

'When I moved in closer to get a better shot, they did not flee but continued on their way at a steady pace."

He added: 'The sharks were able to satisfy their curiosity about me by approaching to the limit of visibility at about six metres distance.

'Although they were swimming in quite a lazy fashion, they are much more streamlined than me. I had to swim quite hard to close the distance and then keep up to continue taking pictures.

'The sharks are known to prey on large seals but I never felt threatened.'

Greenland sharks have been hunted by residents in Iceland and Greenland for centuries.

Their skin is used to make boots while their teeth are turned into cutting tools.

The flesh is part of the national dish of Iceland - called the hakarl.