The arrest of a Democratic congressional intern this week for allegedly publishing the private information of three Republican lawmakers, with police investigating more possible incidents, underscores what has become an increasingly confrontational approach by the anti-Trump 'resistance.'

Jackson Cosko, who recently worked as an unpaid intern for Rep. Sheila Jackson Lee, D-Texas, was arrested for posting the personal information of Sens. Lindsey Graham, R-S.C., Mike Lee, R-Utah, and Orrin Hatch, R-Utah on Wikipedia -- including their home addresses. Fox News learned Wednesday that Capitol Hill police are investigating additional doxxing incidents involving at least two senators, including Sen. Rand Paul, R-Ky. It was not clear if Cosko -- who worked with other Democratic lawmakers including Sen. Dianne Feinstein, D-Calif., Sen. Maggie Hassan, D-N.H., and former Sen. Barbara Boxer, D-Calif. -- was involved.

Cosko had worked in a host of roles in the House and Senate, including as press assistant and legislative correspondent, according to his LinkedIn page.

Former Utah Rep. Jason Chaffetz said on Fox News' "America's Newsroom" Thursday that the wide range of charges against Cosko, including witness tampering and burglary, suggests there could be more to the case than meets the eye.

“With seven different charges out there, it really does makes it sound like it’s more sophisticated and widespread because now you see Sen. Rand Paul is also having issues,” he said, although he added that it wasn't clear if Cosko was connected to the Paul case.

CAPITOL POLICE PROBE ADDITIONAL DOXXING INCIDENTS TARGETING SENATORS, INCLUDING RAND PAUL

While it was not clear what the motivation was behind the posting of personal information (known as "doxxing"), Graham, Lee and Hatch have been outspoken defenders of Supreme Court nominee Brett Kavanaugh amid sexual assault allegations against him. The doxxing on Thursday came moments after Graham had scorched Senate Democrats in a fiery speech for what he called “an unethical sham” in their treatment of Kavanaugh.

The incident marks the latest in escalating attacks against Republican lawmakers and Trump administration officials -- particularly in relation to the Kavanaugh controversy -- by far left-wing activists, which have occasionally picked up the support of Democratic lawmakers.

A day after the doxxing, two female activists cornered Sen. Jeff Flake, R-Ariz., in an elevator on Friday and screamed at him, with one of them repeatedly demanding he look at her as she accused him of suggesting her own sexual assault “doesn’t matter.”

Moments later, Flake demanded an FBI investigation into the accusations against Kavanaugh -- forcing GOP leaders, faced with little room for error on Senate votes, to accede. It was not clear if the dressing down caused Flake to waver, but he later told The Atlantic that the incident “struck a chord.”

Days earlier on Monday, Sen. Ted Cruz, R-Texas, and his wife Heidi were hounded out of a restaurant by protesters peppering the senator with questions about Kavanaugh and chanting “we believe survivors” and “cancel Kavanaugh.” His Democratic opponent in the Texas Senate race, Beto O'Rouke, condemned the incident and said his family "should be treated with respect."

TED CRUZ HECKLED BY RADICAL PROTESTERS IN DC RESTAURANT

The tactic of hounding lawmakers and Trump officials out of restaurants became more prevalent in June, when White House Press Secretary Sarah Sanders and Homeland Security Secretary Kirstjen Nielsen were driven out of restaurants amid the backlash over the separation of illegal immigrant families at the border.

That move was encouraged by Rep. Maxine Waters, D-Calif., who days later called on supporters to confront Trump officials in public spaces.

“If you see anybody from that Cabinet in a restaurant, in a department store, at a gasoline station, you get out and you create a crowd and you push back on them and you tell them they’re not welcome anymore, anywhere,” she told a crowd.

In July, Sen. Cory Booker, D-NJ., who recently compared himself to Thracian gladiator Spartacus, told supporters to go to Capitol Hill and “get in the face of some congresspeople.”

This week, Republicans have been pushing back against such tactics. Some have pointed to the shooting of Rep. Steve Scalise, R-La., at a Republican baseball practice last year as a reminder of how heated rhetoric can lead to much worse.

Kelley Paul, the wife of Sen. Paul, wrote in an open letter to Sen. Booker, saying that she now keeps a loaded gun by her bed after her family has “experienced violence and threats of violence at a horrifying level.”

“I would call on you to retract your statement,” she said. “I would call on you to condemn violence, the leaking of elected officials' personal addresses (our address was leaked from a Senate directory given only to senators), and the intimidation and threats that are being hurled at them and their families.”

The Daily Caller reported that Sen. David Perdue, R-Ga., and his wife were chased through Reagan National Airport by activists -- who kept yelling at him even as he tried to use the bathroom.

On the Senate floor on Wednesday, Perdue blamed Democrats for inciting such behavior, and read quotes he said were inciting harassment of Republicans in public.

“This is America, but these are the tactics of the Brownshirts in Germany in the 1930s, Mr. President,” he said. “Unacceptable. Totally irresponsible.”

Fox News' Chad Pergram and Bradford Betz contributed to this report.