Sen. Elizabeth Warren (D-Mass.) said in a new interview that the "visceral" response to the killing of UnitedHealthcare CEO Brian Thompson should serve as a warning "to everyone in the health care system," adding that "people can be pushed only so far." “The visceral response from people across this country who feel cheated, ripped off, and threatened by the vile practices of their insurance companies should be a warning to everyone in the health care system,” Warren told HuffPost. “Violence is never the answer, but people can be pushed only so far. This is a warning that if you push people hard enough, they lose faith in the ability of their government to make change, lose faith in the ability of the people who are providing the health care to make change, and start to take matters into their own hands in ways that will ultimately be a threat to everyone," added Warren, a vocal critic of the U.S. health care system. Her comments come after Thompson was shot and killed last week outside a midtown Manhattan hotel where UnitedHealth Group was holding its annual investor conference. Some on social media have responded by expressing frustration with the health care system and celebrating or mocking the killing. Rolling Stone published a report detailing social media posts from users attempting to get the suspect's attention. USA Today also reported that the shooting became a "source of ridicule." Pennsylvania Gov. Josh Shapiro (D) on Monday condemned such reactions that he described as showing a "lack of sympathy" for the chief executive. “In some dark corners, this killer is being hailed as a hero. Hear me on this: He is no hero,” the governor said. Luigi Mangione, the 26-year-old suspected of killing Thompson, has been charged with murder in New York City. He faces five counts, including murder in the second degree, two counts of criminal possession of a weapon in the second degree, one count of criminal possession of a weapon in the third degree and criminal possession of a forged instrument in the second degree, an arrest warrant showed. Mangione reportedly said in a handwritten note that he acted alone. Mangione was arrested Monday on gun charges in Altoona, Pa., according to New York City police, who described him at the time as a “person of interest” in last week’s shooting. Police said a ghost gun, silencer and writings expressing ill will toward corporate America were found on Mangione, which linked him to the crime.