The Northampton Paranormal Group took the photograph on a trip to a field between Clipston and Naseby on the anniversary of The Battle of Naseby last month.

And in a vote by the Chron, 80% of those who responded said they believed it did show a ghost. Since the story was published online it has been picked up by the Daily Telegraph and websites specialising in paranormal activities across the world.

Members said they heard clunking noises as well as sounds like cannonball fire but saw nothing.

However, on arriving home, the group's organiser, Emma Whiteman, said she noticed a strange image in the top corner of one of the pictures, taken with a digital camera.

She said: "The picture was taken about an hour after we heard the noises but we didn't see anything at the time.

"When we saw it, when we were looking back through the pictures, we were gobsmacked.

"We're saying that it's a soldier. Some people can see it sitting on a horse and some people just see it as a walking soldier."

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The Battle of Naseby, a key battle in the English Civil War in 1645, involved about 21,000 troops.

The Royal army under Prince Rupert was beaten by Parliamentary troops under Sir Thomas Fairfax, which effectively marked the end of Royal chances in the war.

The 363rd anniversary of the battle was on June 14 this year, when hundreds of people gathered at the site to see if they could detect any paranormal activity.

Although a handful of viral videos taken on the day have appeared on the internet, none have claimed to have seen any spirits.

Adrian Perkin, an author and 'ghost detective', said he thought the image was a soldier with a musket or pike walking through a gateway.
He said: "If this is genuine it's a very, very, good example.

"It's the best I have seen for many years."

Sceptics said the effect was caused by the camera itself.

Anne Haddon, of The Naseby Battlefield Project, said: "I haven't heard anything like this at the battlefield in all my association with it.
"It's fair to say I'm a bit sceptical.

"I'm not the sort of person to believe in ghosts."