As scandalous as it is that federal employees have been kept from their workplaces because armed intruders have taken over the Malheur National Wildlife Refuge in Oregon, now those staffers are being warned they might be victimized by “paper terrorism.”

An email sent to agency leaders Friday warned that self-appointed judges associated with the right-wing sovereign citizen movement might “try to issue indictments, serve papers, or arrest local officials and/or federal employees.” Those papers would have no legal authority, but would serve to bully workers.

Federal workers in the area also have been harassed while shopping, and their personal information at the refuge has been breached.

The email from the Pacific Northwest Region of the Forest Service in Portland said there are “concerns about the potential for ‘paper terrorism,’ where these individuals might attempt to file liens on property belonging to local officials or federal employees.” The information was meant for dissemination to area Forest Service employees, those with the Bureau of Land Management and the Fish and Wildlife Service, which operates the refuge.

So far, there have been no reports of paper or violent terrorism against federal employees, but they have been targets of intimidation in Burns, Ore., where some employees live. Nearby federal offices, in addition to the refuge, have been closed as a precaution.

“As this issue has developed over the past week, our employees and their loved ones have reported a number of uncomfortable incidences in which unknown individuals from outside the Burns community have driven slowly past or idled in front of their homes, observing the residents and their activities,” said Megan Nagel, a FWS spokeswoman. “In addition, self-identified militia members have tried to engage employees and family members in debates about their status as federal employees. Many of these confrontations are taking place as our employees are grocery shopping, running errands with their families and trying to lead their day-to-day lives. While not direct physical threats, these activities are clearly designed to intimidate.”

Nagel also said the trespassers “have broken into locked files containing personal information, such as names and addresses, of employees, volunteers and businesses that have worked with the Refuge in the past 10 years.”

A sovereign citizen representative could not be located. LaVoy Finicum, one of the Malheur interlopers, said they had no connection to the movement. “There are no sovereign citizens here that I know of at all,” he said by telephone.

The intruders have been allowed to come and go as they please, while law enforcement has made no attempt to evict them, not even making them uncomfortable by cutting utilities.

A 2010 statement from the FBI defines the sovereign movement as a domestic terrorism threat. Sovereign citizens don’t believe they must “answer to any government authority, including courts, taxing entities, motor vehicle departments, or law enforcement.” Yet they “clog up the court system with frivolous lawsuits and liens against public officials to harass them,” according to the FBI. The sovereign citizens also create their own make-believe courts that issue warrants against public officials.

Last year, the Department of Housing and Urban Development inspector general issued a warning about scams in which HUD-owned residential buildings are illegally occupied by sovereign citizens who deed the property to themselves. They claim a “right to arrest or sue employees of the ‘illegitimate government,’ ” the warning said. “They are known for filing nuisance lawsuits or liens against individuals who try to stop their schemes, which have involved in lender, credit card, tax, and loan frauds.”

Although the FBI makes a distinction between armed militias and what it calls the sovereign citizen extremist movement, the inspector general and the Southern Poverty Law Center, which tracks extremist groups, say Terry Nichols, a convicted co-conspirator in the 1995 bombing of Oklahoma City’s Alfred P. Murrah Federal Office Building, was linked to the sovereign citizen movement.

Meanwhile, the two-week standoff continues, with law enforcement officers refusing to comment on calls for them to take action.

Saying “this hostile occupation is a clear act of sedition,” National Federation of Federal Employees President William R. Dougan said federal authorities have “enabled lawlessness to go unchecked in the eyes of the nation and emboldened additional militia sympathizers to descend on the area. Enough is enough. The militants occupying the Malheur National Wildlife Refuge must be arrested.”

One of the intruders, bold enough to drive a government truck into town, was arrested for stealing it. But the invaders remain untouched in a building on the refuge, cozy with the utilities the government has not turned off.

This makes no sense to Rep. Peter A. DeFazio (D-Ore.), who blasted authorities on the House floor Friday.

“Well, the lights and the heat are on at the Malheur National Wildlife Refuge, illegally occupied by ultra-right-wing, anti-government extremists,” he said. “But you have to wonder if the lights are on or anybody is home down there at the Justice Department. . . . It is time for the Justice Department to take some action. Wake up down there.”