Secret history of the Navy SEALS: Intimate photographs that reveal life inside the world of America's most elite warriors

At the bottom of a swimming pool a group of men voluntarily sink with their hands bound behind their backs after instructed to reach their face masks on the floor using only their teeth.There appears little struggle as the men calmly work to complete their task before the next one is issued, most likely making their challenge even harder, but all in a day's training.These are the United States' unsung heroes, the Navy SEALS, an exclusive band of about 2,400 special operators most famously responsible for the 2011 midnight raid that led to the capture of Osama bin Laden.

They are America's James Bonds,' Greg Mathieson recently told Fox News of these elite men he's spent the last six years researching and photographing.They, as well as all other members of special warfare - with there being he says about 20 support personnel for every Navy SEAL out there - appear in his new book: United States Naval Special Warfare.

They have so much gadgets and equipment, the skill level of these guys, an average SEAL out there, has a degree in college. He may speak a couple different language,' Mr Mathieson emphasized.The result of Mr Mathieson's alongside field work is a stunning 931 photograph collection, some exclusive and never-before seen, that he's never been granted permission to release until now.Some chapters are even written by the SEALS themselves.