‘Patriots’: Members of the Sheahan family at Groom Mine in an undated picture: Area 51 can be seen in the background. Picture: Facebook

The family own the 400 acre Groom Mine, which overlooks Area 51, one of America’s most closely guarded military secrets and a mecca for UFO spotters and conspiracy theorists from all over the world.

Located in the Nevada Desert, the military base officially known as “The Nevada Test and Training Range” borders on the Sheahan’s property, which has been in the family since 1889.

The family’s allegations range from illegal government searches and checkpoints to military jet attacks on the mine and a devastating cancer cluster that has seen the premature deaths of several members.

But the final straw — and the one that drove the Sheahans to end an extraordinary six decades of silence — came last month when the US Air Force (USAF) gave them an ultimatum: sell up for $5.2m or watch it seized and destroyed for free.

The family turned them down, claiming the offer was less than half the true value of the land and didn’t come close to compensating for Area 51’s legacy of disease and lost livelihood.

Last week, USAF filed a lawsuit seeking to have the property condemned to speed up acquisition. If successful, the Sheahans will be left with nothing.

“We really didn’t want to come public, but the air force has forced us into it,” Dan Sheahan, who co-owns the mine with cousins Joe Sheahan and Barbara Sheahan-Manning, told Las Vegas Now.

“We want them to know what they have done over the last 60 years to our family is not acceptable.”

The Sheahans say they’ve been held at gunpoint at military checkpoints on the way in and out of their property, which has been in the family since the 1880s. Picture: FacebookSource:

The titanium A-12 spy plane prototype is mounted onto a pylon for radar cross section tests at Area 51 in an undated photo. Picture: FacebookSource:Supplied

The USAF says it wants the land because, after decades of escorting family members in and out of the highly-restricted space, it can no longer ensure their safety.

“We’ve tried to do everything we can, include cancelling missions when they come out,” senior air force commander Colonel Thomas Dempsey said. “And that’s a tremendous expense to taxpayers.”

But Joe Sheahan told CNN that couldn’t be further from the truth.

“I didn’t create this mess, they did,” he said. “They surrounded us. We’re tired of running, tired of hiding. I think that they’re capping off 60-plus years of nothing short of criminal activity.

“What they really want to buy is our property, our access rights and our view. We prefer to keep our property, but it’s for sale under the right price at the right conditions. Why don’t they ask themselves what it cost my family over the years in blood, sweat, tears and money?”

The family’s Facebook page describes them as “ardent patriots” who have tried to be “flexible to the requirements of Area 51”.

“In return, we have received nothing but threats and indignant acts by our own government,” it says.

“The acts of the USAF are an abomination of the ideals on which this country was built: that every American has certain inalienable rights to life, liberty and the pursuit of happiness and, that to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed.

“It’s time that the USAF upheld this notion.”

The abandoned Groom Mine today. Picture: FacebookSource:

The site that would become known as Area 51 can be seen in the distance in this undated photo. Picture: FacebookSource:

The ultra-classified facility has swallowed up close to three million acres of surrounding land since USAF realtors started buying up in the 1940s. It was around this time that Groom Mine property was sprayed with bullets from overhead aircraft in the first effort, the family says, to intimidate them into leaving.

The mine was functioning and prosperous until the mid-50s when the base was built and the USAF started conducting nuclear weapons experiments and U-2 spy plane tests, and amped up the scare tactics.

But the Sheahans stayed, operating a ore processing mill until it mysteriously exploded in 1954, ending production permanently. The family believes the mill was destroyed by an “errant bomb” or “aircraft engine” that fell from the sky. They cite a fire inspector’s letter that “a foreign object or device may have been instrumental.”

They sought compensation from the government but ran out of money to see the lawsuit through. It would be the last time they would use lawyers.

A 1959 letter from Ms Sheahan-Manning’s parents, Daniel and Martha Sheahan, to the then-U.S. Attorney General William P. Rogers blamed the mine’s demise on radioactive fall out and the mill’s destruction process.

The air force had “intentionally using our property for military test purposes and then forcing us to bring suit in order to try to protect ourselves,” the letter stated.

It was the start of a 60 year war between the USAF and the Sheahans, who claim they have been sporadically held at gunpoint while visiting their property.

The Sheahans claim a 1986 environmental study estimated Groom Mine’s worth to be more than US$13 million.

The US air force says it wants the Sheahan land to establish a secure buffer zone for Area 51. Picture: SuppliedSource:

The Extraterrestrial highway was established in 1996 and runs along the eastern border of Area 51Source:News Limited