Two days after Charlie Kirk was killed, Suzanne Swierc, an employee at Ball State University in Muncie, Ind., woke up to a cascade of missed calls, texts and voice mail messages from numbers she did not know.

“They were calling me all kinds of names, threatening my job,” Ms. Swierc said. “It was every awful curse word under the sun.”

“I immediately texted my supervisor, and I said, ‘I think I have a situation.’”

Ms. Swierc (pronounced swirtz) discovered that the barrage stemmed from something she had posted on Facebook the day before: “If you think Charlie Kirk was a wonderful person, we can’t be friends.” Her Facebook settings were private, but one of her followers must have taken a screen shot and sent it on without her knowledge.

Within hours, Libs of TikTok, a social media account known for transphobic content and smear campaigns against schools, hospitals and libraries, posted it publicly on its popular X account. Ms. Swierc got her first message 19 minutes later. Elon Musk posted about it. So did Rudy Giuliani. Indiana’s Attorney General, Todd Rokita, also mentioned it on X, calling her comments “vile,” and saying that they “should make people question someone’s ability to be in a leadership position.”

When someone from a Buffalo area code left a voice mail message stating Ms. Swierc’s home address and saying maybe she “should get the same treatment as Charlie,” Ms. Swierc called the police. Eventually, the post would get 6.9 million views.

The experience, Ms. Swierc said, affected her physically.