Jerome Adams, who served as U.S. surgeon general in President Donald Trump’s first administration, on Sunday issued a forceful rebuke of Health and Human Services Secretary Robert F. Kennedy Jr.’s response to a recent shooting at the headquarters of the U.S. Centers for Disease Control and Prevention in Atlanta.

The man who, according to law enforcement, believed the COVID-19 vaccine was responsible for making him depressed, shot dozens of rounds across the CDC’s campus on Friday, killing one police officer. The shooter also died at the scene but it was unclear if he killed himself or was killed by police.

In an interview with CBS’s “Face the Nation,” Adams said Kennedy’s reaction was inadequate, while also taking issue with his past criticism of the agency and his questioning of the safety and efficacy of vaccines.

“How you respond to a crisis defines a leader,” Adams said. “And quite frankly, Secretary Kennedy has failed in his first major test in this regard. It took him over 18 hours to issue a tepid response to these horrific shootings, and that’s not even considering how his inflammatory rhetoric in the past has actually contributed to a lot of what’s been going on.”

Kennedy addressed the shooting on Saturday in a post on X, writing: “No one should face violence while working to protect the health of others. We are actively supporting CDC staff on the ground and across the agency. Public health workers show up every day with purpose — even in moments of grief and uncertainty.”

Kennedy, a prominent vaccine skeptic, has previously labeled the CDC a “cesspool of corruption” and claimed the agency’s effort to vaccinate children ignored vaccines’ harms to children, likening the approach to the cover-up of child sexual abuse by the Catholic Church.

Adams said some of Kennedy’s past comments could lead to violence.

“While I don’t know Secretary Kennedy personally, and I don’t want to make assertions about his character, I will say, based on his actions and his rhetoric, he’s fanning the flames that lead to situations like we saw at the CDC,” Adams added.

Adams previously criticized Kennedy’s decision to pull millions in funding for projects to develop vaccines using mRNA technology, saying the move “is going to cost lives.”

Kennedy has also pulled the CDC’s recommendations for healthy children and pregnant women to receive the COVID shot.