Satellites are being used to provide 24-hour security for the royal shipwreck found off the Norfolk coast, amid fears looters could plunder its treasures.

The discovery of the Gloucester - which sank in 1682 with the future James II on board - was revealed last week and made headlines around the globe.

It has been described as one of the world's most significant shipwreck finds in decades and experts believe it is laden with artefacts.

Some have been brought to the surface already and there are plans for future diving expeditions onto the wreck to learn more of its secrets.

But the team behind its discovery fear the site could become the target of unauthorised exploration and have put security measures in place to protect it.

Julian Barnwell, one of two brothers from Wroxham who found the ship, said: "There is always the potential threat of looting. That is something we are all very conscious of."

The precise location of the wreck has been kept secret, although the ship is known to have sunk after running aground on the Leman and Ower sandbank, around 45km off the coast of Great Yarmouth.

Amid concerns that looters could try to locate and then dive on the remains, the wreck site is being constantly monitored by satellites, which can detect suspicious shipping activity in the area.

Mr Barnwell also said that there was "people out to sea permanently off shore" who were helping to keep an eye on it.

He added he hoped anyone tempted to rob the site would understand the wreck was in the expert hands of people best-placed to do marine archaeology and study the finds, as well as properly tell the story to the nation.

The timing of Friday's announcement came as the team was satisfied they were "in a good place" in terms of security, to tell the world about the "at risk" site, which lies in international waters.

Even the depth of the wreck is considered too much of a clue and that detail is being kept under wraps.

Mr Barnwell and his brother Lincoln are preparing to dive the wreck for the first time this season.

So far everything found has been lifted to the surface from the seabed without any deep trench digging.

Because the seabed was so 'dynamic' it was different every time, he said, adding: "That's what makes it so exciting."

Just a tantalising snapshot of the hundreds of items said to have been found have been released ahead of a planned exhibition at Norwich Castle Museum next year.

They include a pair of glasses still in their case, some 30 bottles of wine, clothes and shoes, navigational and other professional naval equipment, and personal possessions.

One of the bottles bears a glass seal with the crest of the Legge family - ancestors of George Washington, the first US president.

The crest was a forerunner to the Stars and Stripes flag.



What lies beneath

Just how much remains of the ship is not clear, but a mound of sand at what would be the stern could be the preserved remains of the personal quarters of the Duke of York, as James II was at the time.

This area of the ship is known as "the king's castle" and the interior would have been richly decorated in gold leaf.

There are hopes that some of that could still be in place, along with the duke's possessions, possibly still unpacked in trunks.

The Duke was rescued from the sinking ship by another vessel accompanying the Gloucester. Up to 250 of the crew perished, though.

What is known, Prof Claire Jowitt told Dan Snow in his History Hits podcast, was that the duke did rush for his memoirs in a bid to protect his reputation, delaying the evacuation.

As it was his character was tarnished by the whole Gloucester episode with questions about his role in the tragedy, his indecisiveness, and willingness to blame others helping to make the case against him.

For the Barnwell brothers it has always been about the spirit of adventure and the thrill of the quest.

They first started looking for the wreck in 2003 and found it four years later - a giant metal detector called a magnetometer picking up a cannon on the seabed and sending its location to a computer.

On the day, Julian, who usually did the diving, was nursing a hernia, so it was Lincoln who saw the ship's shadowy shape for the first time.

He has now described multiple times the "awe- inspiring and really beautiful" moment it emerged from the gloom.

He said: “It instantly felt like a privilege to be there, it was so exciting. We were the only people in the world at that moment in time who knew where the wreck lay. That was special and I’ll never forget it."

Also on board that momentous day was their father, who first got them into diving, and their friend James Little, making the day extra special.