The administration is putting together plans to take action against left-wing groups that President Donald Trump and his allies accuse of fomenting political violence, according to three people familiar with discussions about the federal response to the Sept. 10 assassination of conservative activist Charlie Kirk in Utah. One of the sources said the moves could come as early as the end of the month.

The White House is “trying to move quickly while not rushing,” the person added.

The actions, which are still being formulated, are expected to include investigations into the tax-exempt status of certain liberal organizations, the same source said. They were first reported by the Wall Street Journal.

“The White House is exploring a wide variety of options to address left wing political violence and the network of organizations that fuel and fund it,” an administration official said. “The emphasis and focus are on criminal actions,” the official added, “not political speech.”

Trump told “Fox & Friends” last week that he wanted to launch a racketeering probe of groups funded by billionaire George Soros, a 95-year-old New York-based financier. The president later told NBC News that Soros “should be put in jail.”

As the guest host of “The Charlie Kirk Show” on Monday, Vice President JD Vance said that the administration would look into the Soros-founded Open Society Foundations and the Ford Foundation.

“Do you know they benefit from generous treatment? They are literally subsidized by you and me, the American taxpayer,” Vance said. “And how do they reward us? By setting fire to the house built by the American family over 250 years.”

Federal law prohibits the president and vice president from ordering inquiries into groups’ tax status, and neither Trump nor Vance has presented evidence linking those groups to Kirk’s death. But the administration argues that it resulted from what White House deputy chief of staff Stephen Miller called “a vast domestic terror network” funded by liberal philanthropists.

“We are going to use every resource we have at the Department of Justice, Homeland Security,” Miller said in an interview with Vance on the Kirk show.

Utah County Attorney Jeffrey Gray laid out seven criminal charges — including aggravated murder — against Tyler Robinson in a news conference Tuesday, and detailed the evidence against him in a 10-page court filing. There was no indication presented Tuesday that the suspect was a member of a group. The investigation is ongoing.

The administration official said federal authorities may explore groups alleged to have spurred riots and attacks on law enforcement officers, groups that engage in illegal doxxing campaigns — where personal information is made public — and anyone responsible for “drop points for weapons and material.”

That work is in the early phase of planning and is not expected to be operationalized immediately, two of the sources familiar with the matter said.

The desire to respond to Kirk’s death with policies that dismantle parts of the political left — driven by a mix of grief, fear and anger among conservatives — is palpable within Trump’s MAGA movement.

“There are a lot of groups working on what our response will look like at the state level and then the federal level,” said Rachel Bovard, vice president of programs at the Conservative Partnership Institute and an ally of the Trump administration, in a phone interview. “It’s almost the entire right. I don’t think people realize how deeply just in grief the right is.”

She described a pall hanging over conservatives and a sense of urgency.

“This isn’t like ‘how can we score political points?'” she said. “It feels existential, and it feels like there is a target on all of us right now.”

A set of more than 100 progressive philanthropic organizations wrote an open letter Wednesday denouncing political violence, including the recent killings of Kirk and former Minnesota House Speaker Melissa Hortman, a Democrat, and pushing back on the crackdown Trump has promised.

“We reject attempts to exploit political violence to mischaracterize our good work or restrict our fundamental freedoms, like freedom of speech and the freedom to give,” the groups, which include the Open Society Foundations and the Ford Foundation, wrote. “Attempts to silence speech, criminalize opposing viewpoints, and misrepresent and limit charitable giving undermine our democracy and harm all Americans.”

Some on the right are also calling for the implementation of more extreme measures to restrict the funding and activities of liberal groups.

Steve Bannon, host of the “War Room” podcast and a senior White House aide in Trump’s first term, told NBC News in a text message that he believes the administration should “designate ANTIFA and others ‘terrorist organizations'” to shut them down. “Designation gives you a full tool box.”

Trump said on Truth Social Wednesday night that he is designating antifa as a “MAJOR TERRORIST ORGANIZATION,” adding that he “will also be strongly recommending that those funding ANTIFA be thoroughly investigated in accordance with the highest legal standards and practices.”

There are numerous federal laws that criminalize domestic terrorist activity, but only foreign groups can be designated as “terrorist organizations,” a label that makes it illegal to provide support to them. The Trump administration has designated several foreign drug cartels and gangs as terrorist organizations this year in its effort to combat trafficking. But applying the designation to U.S.-based groups could require a change in federal law.

There are signs that Trump administration officials are sensitive to concerns that the response to Kirk’s death could chill free speech — concerns that have been expressed by liberals and conservatives alike.

During a speech in Michigan Wednesday, Vance appeared to try to strike a balance.

“I want to let you know that whether you’re a Democrat or Republican, whatever your belief is, I will fight for your right to speak your mind,” he said. “We reject political violence, and we reject the crazy left-wing radicals that gun down our friend Charlie Kirk. Let’s talk to one another and not try to shoot each other down for disagreeing.”

Utah officials are seeking the death penalty against Robinson if he is convicted. Robinson hasn’t yet been appointed an attorney to represent him.