The first man who knocked on the Fauquier County woman’s door told her they had been e-mailing and he was there for sex. Shocked and perplexed because they hadn’t corresponded, the woman sent him away.

But the men kept coming. They arrived on her doorstep as many as six times a day, sometimes traveling from other states. One had a crowbar. Others refused to leave. Another rammed his car through a security gate that she installed.

In all, there were about 100. Each said he had communicated with her. All expected sex.

The unrelenting onslaught was organized by an angry ex-boyfriend, who had assumed the woman’s identity online and crowdsourced his harassment to dozens of unwitting accomplices he lured to her home, prosecutors say in court papers.

The case, which goes to trial next month in federal court in Virginia, is among a number around the country in which stalkers are accused of stealing their victim’s online persona and using the power of social media as a weapon.

The Fauquier County woman thought it was only a matter of time before she was assaulted, raped — or worse. She turned her home into a fortress with security cameras, floodlights and a gate.

“I live in fear of anyone coming to my door,” the woman said. “I’m a prisoner in my own home.”

A relationship sours

Things began very differently.

The 64-year-old retired protocol officer for the Department of Defense lost her husband in 2009. The woman asked not to be named for fear of continued harassment.

She met Kenneth Kuban, a film preservationist at the Library of Congress, on a dating site in 2010. Like her, the 61-year-old worked for the government and had also recently lost his spouse. It seemed like a good match.

But she quickly realized they were not compatible. He used her barbecue grill as an ashtray and drank directly out of her milk container, court papers say. He had unusual proclivities in bed.

“He was just a Neanderthal type of man,” the woman said during a pre-trial hearing.

When she ended the relationship in February 2011, he responded with a barrage of daily phone calls and e-mails that continued for four months, according to prosecutors. He begged her to come back, but she said she ignored him.

She got a restraining order in July 2011.

Then Kuban, who has no criminal record, took to the Web, authorities said.

Another knock at the door

For a Prince George’s County woman, the nightmare began the same way — with a knock at the door.

The man on her doorstep last June told her she had invited him over for sex during an instant-message chat, according to court documents. She had no idea what he was talking about and told him she was not interested.

The 33-year-old mother of four had divorced Michael Anthony Johnson II, an unemployed computer specialist from Hyattsville, in 2011. Their relationship was tempestuous.

Johnson went to her home one night in 2011, got in her car and waited for her until the next morning. When she got in, Johnson wrapped his hands around her neck. She escaped, and Johnson was convicted of assault.

Now, she believed Johnson had her in his sights again. When she logged onto Craigslist in the days after the man showed up at her home, she found ad after ad. They had increasingly vile titles including one that read: “Rape Me and My Daughters.”

When she clicked on the ad, her photo popped up and her address was listed.

“My stomach just went into a knot,” the woman said.

Rare, but growing

Experts say Internet impersonation remains rare, but recent cases have prompted about a half-dozen states including Texas, New York and California to pass laws criminalizing it. Maryland and Virginia are not among them.

In Texas, two Hood County middle school students were arrested in 2012 for creating a fake Facebook profile for a fellow student and using it to threaten other students. In 2011, a 22-year-old Los Angeles man was convicted of creating at least 130 fake social media accounts to harass his former girlfriend.

To combat the problem, Facebook has created a reporting system to flag fake accounts. Craigslist did not respond to repeated requests for comment.

Hemanshu Nigam, a former federal prosecutor who handled computer crimes and founder of Internet security company SSP Blue, said Internet impersonation stalking will probably only increase as more people become comfortable with social media.

He believes the Internet has also emboldened some stalkers.

“They are using the anonymity of the Internet to do things they would never do offline,” Nigam said.

Virtual terror

The Fauquier County woman’s tormentor used Craigslist, too. Kenneth Kuban is accused of posting salacious ads posing as the woman in the “Casual Encounters” section. One read:

“I’m a senior lady who is looking for some fun

And ad­ven­ture in my life!!

Would like to meet a gentleman in his 50s that . . .

can give me some pleasuring.”

The woman said the ad and at least 50 others were posted between January and March 2012. She flagged them as inappropriate, but it sometimes took two days for Craigslist to remove them.

It did little to slow the flow of men to her door. They came from as far as North Carolina and West Virginia. The woman called the Fauquier County Sheriff’s Office to chase them away — sometimes several times a day.

In March, the woman reported the harassment to the Library of Congress, which began investigating its employee. An agent with the Office of the Inspector General responded to one of the ads.

“Can we meet up today?” the agent asked, according to court records.

“Sure can here’s my address” the poster wrote back. “Just a side note my gate has been giving fits you may have to park and walk up my lane, sorry.” It was signed “Love” and the woman’s name. A photo of the woman was attached.

Investigators later determined that the message was sent from an IP address at the Library of Congress’s facility in Culpeper where Kuban worked and that his e-mail was used to post ads on Craigslist, according to court records.

Kuban was arrested and charged with stalking, identification fraud and other counts. If convicted, he faces a maximum of five years in prison. His attorney declined to comment.

The Fauquier County woman said she worries what might happen if her ex-boyfriend is acquitted or when he is released after completing any potential sentence.

A digital assault

The scope of the attack against the Prince George’s County woman was even more frightening.

The day after she discovered the “Rape me” listing, another ­stomach-churning ad was posted. It offered her then-12- and 13-year-old daughters and 12-year-old son up for sex in exchange for cash. The children’s photos appeared in the ad.

But the digital assault was just beginning. The woman found fake profiles for herself on a host of sites including Facebook and the pornography aggregator XTube, soliciting men for sex and listing her address.

The men showed up at her door at all hours. Some prompted by the bogus “Rape me” posting tried to break into her home, according to court records. There were professional men in suits and some in uniform — at least 50 during a two-week stretch during June and July 2012.

The woman said she purchased a shotgun and stayed up nights with it pointed at her front door, as her kids dozed in the living room. She said they were too scared to sleep in their own beds.

She got a restraining order against Johnson, who was also sending her threatening e-mails. She said she spent days trying to get sites to remove the fake profiles. Some took them down quickly, but she was forced to send others copies of her ID, letters and her protective order case number before they would remove them.

She said she prepared her children for worst-case scenarios.

“I told them this could end two ways: Mommy’s going to die protecting you or mommy’s going to shoot someone,” the woman said.

The campaign culminated on the night of July 22, 2012, in a chilling display of Johnson’s ability to manipulate. The woman received e-mails she believed came from her ex-husband saying he was coming to kill her and he would be outside her apartment honking the horn of a red pickup truck.

She glanced out her window and saw a man in a truck. He was honking the horn. She called police, and officers discovered it wasn’t her ex-husband in the pickup, but yet another man he had tricked into coming to her home expecting sex.

Johnson was arrested soon after and stood trial in June. He was convicted on more than 70 counts, including stalking, reckless endangerment and dozens of violations of a protective order in Prince George’s County court. He faces up to 115 years in prison when he is sentenced on July 18. His attorney declined to comment.

The Prince George’s County woman said Internet impersonation has irrevocably changed her life.

She moved and pulled her children out of their schools. She found a new job, but it pays less and barely covers her bills. She is still fighting to have some of the fake material removed from sites and search engines. It frustrates her.

“Many people think you can ignore stuff that’s posted online,” she said. “There becomes a point, though, when virtual reality becomes reality, and it ruins your life.”