A memorial commemorating Nazi spies remains in storage at a National Park Service facility outside Washington. A white supremacist group placed the stone on federal land decades ago. (Photo by Bonnie Jo Mount/The Washington Post)

A team of power company workers was trudging through a seldom-visited thicket in Southwest Washington when they spotted something odd in a ditch.

Protruding from the grass was a rectangular slab of granite.

They looked closer, and an inscription on the surface came into focus. What they saw astonished them.

It was a memorial. In honor of Nazi spies. On U.S. government property.

“In memory of agents of the German Abwehr,” the engraving began, “executed August 8, 1942.”

Below that were six names, and below those was another cryptic line: “Donated by the N.S.W.P.P.”

News of the unsettling discovery soon reached Jim Rosenstock, who worked in resource management for the National Park Service and also happened to be a local history buff. He was curious, but also skeptical. How could someone have planted such an item there? And why? And — above all — who?

Rosenstock needed to see it for himself, so he, too, made the hike into Blue Plains, a woody area known best for a wastewater treatment plant and an abundance of mosquitoes. And that’s when he saw the stone.

“I kind of started doing a little bit of my own research,” Rosenstock recalled of that day in 2006 when he began to help unravel an only-in-Washington mystery, complete with World War II espionage, nationwide panic, a mass electrocution, J. Edgar Hoover chicanery, white supremacists, classic federal bureaucracy and a U.S. Supreme Court case that played a significant role in America’s modern war on terror.

***

For decades, very few people in Washington, or elsewhere, knew of the stone’s existence. It wasn’t a secret so much as something that just never got out — remarkable in a town famous for its leaks.

Only when a former Park Police detective mentioned it in passing to a Washington Post reporter, then provided photographic evidence, did anyone ask the Park Service about it.

[Hitler’s mother was ‘the only person he genuinely loved.’ Cancer killed her decades before he became a monster.]

A spokeswoman referred the Post to the now-retired Rosenstock, because perhaps no one has thought more about the 31-by-26-by-8-inch object than he has.

At the start of World War II, Rosenstock discovered when he began his research, Adolf Hitler had been determined to show the world just how susceptible America was to a Nazi attack, so he ordered his military to devise a plan.

The high command, according to a 2002 Post story, recruited eight Germans for the mission. In teams of four, the men were loaded onto a pair of U-boats, one destined for Jacksonville, Fla., and the other for a beach near the tip of Long Island.

On June 13, 1942, the New York group reached shore — and was almost immediately discovered by an unarmed Coast Guards member on foot patrol. The men escaped, but by morning, the Coast Guard had unearthed the Germans’ buried supplies: fuses, pre-made bombs and four crates of TNT.

That wouldn’t have mattered to their leader, George John Dasch, who hadn’t intended to wreak devastation on Hitler’s behalf anyway. When the group reached New York City, he and a comrade decided to turn the others in, so Dasch phoned the FBI.

Four days later, he took the $82,000 he’d been given for the operation — more than $1 million in today’s money — and boarded a train for Washington. There, he met with FBI agents, whom he expected to welcome him as a hero.

They didn’t.

J. Edgar Hoover, the infamous head of the bureau, recognized an opportunity. In late June, with all eight men caught, Hoover announced their capture in New York — and claimed credit for his agency.

He made no mention of Dasch.

“The country went wild,” Francis Biddle, then attorney general, later wrote in a memoir.

Hundreds of German aliens were rounded up and others, suspected of spying, were arrested. The Justice Department banned German and Italian barbers, servers and busboys from Washington’s hotels and restaurants because three of the would-be saboteurs had worked as waiters in America.


The special seven-man military commission opens the third day of its proceedings in the 1942 trial of eight Nazi saboteurs in the fifth floor courtroom of the Department of Justice building.  (Library of Congress)

Ignoring due process, President Franklin Roosevelt ordered that the men be tried in secret before a military commission — a tactic, then backed by the U.S. Supreme Court, that President George W. Bush would replicate 59 years later in his directive that Guantanamo Bay detainees be judged in a similar fashion.

In mid-summer 1942, seven U.S. Army generals found all eight men guilty but left their punishment to the president. He sentenced six to death and two, including Dasch, to lengthy prison terms (both were deported after the war).

The electrocutions began at 12:01 p.m. on Aug. 8. By 1:04, all six were dead.

Three days later, they were secretly buried amid a seldom-visited thicket of Southwest Washington known as Blue Plains.

***

Rosenstock quickly learned the backstory of the six Nazi spies listed on the stone, but another question remained: Who had placed it there?

The line at the bottom — referencing the “N.S.W.P.P.” — offered a clue.

Until the mid-1960s, the National Socialist White People’s Party had gone by a more familiar name: the American Nazi Party. According to the Southern Poverty Law Center, the group’s founder, George Lincoln Rockwell, had given it the new title shortly before his assassination in 1967.

By the 1970s, though, the group had begun to split apart and had lost much of its relevance, leading Rosenstock to believe the Nazi memorial dates back to that time.

The party didn’t entirely cease to exist until 1983, the law center said, so the stone may had been carved more recently — though that still means it likely sat on Park Service land for more than two decades before the power company’s discovery.

[Hitler refused to use sarin gas during World War II. The mystery is why.]

For Rosenstock and his colleagues, the memorial presented a conundrum. It was deplorable, and certainly not something that belonged on public property, but none of their handbooks suggested how to deal with a 200-plus pound monument to Nazis installed on public land by white supremacists.

Plus, the Park Service couldn’t do anything until they were sure it hadn’t been placed atop someone’s bones.

What if, they wondered, the Nazis were buried beneath it?

The Park Service scoured World War II-era records for details on their bodies, but researchers could find nothing that provided a definitive answer. Old maps showed conflicting spots, including one beneath a building.

“The location is a little bit confusing,” he said, “and I think deliberately so.”

Rosenstock suspected that whoever disposed of the spies’ bodies didn’t want them found.

What he did learn, though, is that no one was buried beneath the stone because a creek had run through that area in the 1940s.

Still, the Park Service hadn’t decided what should be done.

“It was an illegal monument,” Rosenstock said. “And we certainly did not want to be hosting a site for midnight rituals on Hitler’s birthday.”

That was a legitimate concern. Rosenstock once found deer bones arranged atop the memorial. Others had found candles around it and noticed that it was regularly cleaned.

“At least one fellow in the Park Service suggested breaking it up with sledge hammers and throwing it in the river,” he recalled. “It’s not the argument that historic preservationists make.”

The memorial remained intact.

In 2010, under the direction of a museum curator, a forklift exhumed the granite block and lowered it into a truck.

The stone, tagged OXCO-475, now spends its days beneath a protective blanket on a shelf at a storage facility in suburban Maryland. Park Service staff asked that The Post be no more specific than that because, though they didn’t mind its long-unknown story being told, they’d prefer that its exact location remain a secret.

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