Comet Ping Pong customers came out to support the restaurant after a gunman entered it with an assault rifle, firing it at least once. Several other businesses on the block have received other threats as well. (Whitney Shefte/The Washington Post)

Shaken by weeks of death threats and online attacks fueled by a bizarre conspiracy theory, the independent business owners on this block of Connecticut Avenue in Northwest Washington gathered at Terasol restaurant just after Thanksgiving to discuss what to do. Though they had repeatedly reported the harassment to District police and the FBI, the abuse had only intensified.

Terasol’s co-owner, Sabrina Ousmaal, who had begged authorities for help, worried that the worst was yet to come.

“It only takes one crazy with a gun,” she recalled saying at the meeting.

On Sunday, police say, a North Carolina man with an assault rifle walked into Comet Ping Pong, the pizzeria across the street that had become the subject of a widely shared fake news story linking Hillary Clinton to a child sex ring. He fired his gun at least twice before pointing it at an employee.

Edgar Maddison Welch, 28, walked into D.C. pizza restaurant Comet Ping Pong armed with an assault rifle on Dec. 4, apparently to "investigate" a fake internet conspiracy. Here's what we know about him so far. (Deirdra O'Regan/The Washington Post)

The man, Edgar Maddison Welch, would later tell police he had come to rescue imprisoned children who, of course, didn’t exist. Ousmaal’s husband, Alan Moin, was driving down Connecticut Avenue NW just after Maddison had gone inside the pizza shop. An officer yelled at Moin to back up, so he made a U-turn and parked in front of his own restaurant. Suddenly, people poured out of Comet, screaming.

“I knew exactly what was going on,” he said.

Internet trolls had first targeted Comet after WikiLeaks revealed that its owner, James Alefantis, had communicated with Clinton’s campaign chief, John Podesta. Inexplicably, those hacked emails morphed into the false allegations against Alefantis and Clinton.

Soon, the conspiracy theory grew, and so did the fallout on Connecticut Avenue.

A few days before the election, Ousmaal noticed a disturbing Google review of the restaurant. It alleged that they, too, were involved in the sex-abuse plot. More online accusations quickly followed.

They suspected that the online mob may have targeted them because of a photo on Terasol’s website that showed Ousmaal and her daughter posing with Clinton, who had eaten there three or four years ago.

The would-be Internet sleuths also fixated on a heart logo that appeared on the site as part of a fundraiser for St. Jude Children’s Research Hospital, which Ousmaal, a cancer survivor, has supported for years.

“These maniacs thought that was a symbol of child pornography,” Moin said Monday. “It’s crazy.”

When the family removed it from the site, their tormenters concluded Terasol was hiding something. The anonymous calls increased.

Just up the road, Abdel Hammad’s Besta Pizza was swept up in the witch hunt shortly after the election, when the company that maintains his website alerted him to an astonishing new review. Someone had alleged that his shop’s simple, pizza-shaped logo was also a symbol of child pornography.

He was stunned.

“It’s a slice of pizza,” Hammad said.

He removed the logo from his site but couldn’t afford the more than $2,000 to pay for new signs.

“Why did you change the website?” anonymous callers began screaming at him over the phone.

“We’re going to put a bullet in your head,” threatened another.

Last week, Hammad said, a pair of protesters barged into his shop and photographed a manager, who broke his fingers when he tried to stop them.

More than once, he’s had to turn off the phones at his two stores, including one in Bethesda. His revenue, he said, has plummeted by 35 percent.

“I’m just an immigrant running a pizza place trying to make ends meet,” said Hammad, a Muslim — and Donald Trump voter — who moved here from Egypt in 1980 and first opened a pizza joint on Connecticut Avenue 25 years ago. The business helped send his daughter to Penn State and his oldest son to Virginia Tech, where he has joined the Army ROTC program.

“If it goes like this another month or two,” Hammad worried, “I’m going to have to shut down.”

Several doors down, Politics and Prose has also been inundated with online hate and a relentless stream of vicious calls since mid-November, and like his neighboring entrepreneurs, the bookstore’s co-owner, Bradley Graham, was frustrated with the police response.

“We had felt for days,” he said, “that more could and should have been done to squelch these verbal attacks and figure out who is the source.”

Ousmaal first reported the harassment of her restaurant to D.C. police two weeks ago, but in emails she shared with The Post, an officer told her they couldn’t do anything to prevent free speech. He suggested she file a lawsuit.

She understands freedom of speech, Ousmaal replied in an email, but “derogatory libelous and hateful blogs and emails should not and cannot qualify.”

The officer replied once more, suggesting she ask the other owners if they knew who was behind the “disruption.”

“I don’t have anymore options to give unfortunately,” he wrote.

Ousmaal couldn’t believe it. She feared her family or staff could be harmed.

“Literally,” she said, “death threats.”

In a statement, District police maintained that they “did not receive reports of any specific threats” before this weekend’s incident.

But Ousmaal was encouraged on Monday evening after she and the other business owners met with city and police leaders, who promised to provide the neighborhood with more security and to pursue those responsible for the harassment.

Their message was simple, she said: “We’re going to do something.”

Susan Svrluga contributed to this report.