Rep.-elect Mark Green (R-Tenn.) is walking back comments at a town hall in which he promoted the conspiracy theory that vaccines cause autism and said that the Centers for Disease Control and Prevention may have “fraudulently managed” data on the topic.

Green, a physician who last month won the House seat being vacated by Rep. Marsha Blackburn (R-Tenn.), made the remarks Tuesday night in response to a question from a town hall attendee.

“Let me say this about autism,” Green said, according to a video of the exchange posted by the Tennessean. “I have committed to people in my community, up in Montgomery County, to stand on the CDC’s desk and get the real data on vaccines, because there is some concern that the rise in autism is the result of the preservatives that are in our vaccines.”

He added that, as a doctor, he could approach the issue “academically” and make his case against the CDC “if they really want to engage me on it.”

“But it appears that some of that data has been, honestly, maybe fraudulently managed,” he said.

In a statement Wednesday night, Green said that his comments about vaccines had been “misconstrued.”

“I want to reiterate my wife and I vaccinated our children, and we believe, and advise others they should have their children vaccinated,” he said.

The modern anti-vaccine movement has its roots in a 1998 study that used falsified data to claim a link between childhood vaccines and autism. The study was later retracted, and the author’s medical license has since been revoked; even so, some figures on both the far left and the far right have embraced the widely discredited theory.

The percentage of children under 2 years old who don’t receive any vaccines has quadrupled in the past 17 years, according to the CDC. The emergence of “hotspots” in the United States where increasing numbers of parents are hesitant to have their children immunized has also prompted alarm among researchers, who warn that children in those areas are at higher risk for pediatric infectious diseases such as measles and whooping cough.

Peter Hotez, dean of the National School of Tropical Medicine at the Baylor College of Medicine, said that it was shocking that a newly elected congressman “would openly espouse such blatant antiscience and discredited views.”

“The science is clear: Vaccines do not cause autism or the other things the antivaccine lobby alleges,” said Hotez, whose recent book, “Vaccines Did Not Cause Rachel’s Autism,” draws on his experience as a vaccine expert and the father of an autistic child.

He added that without Green’s “immediate reaction and heartfelt apology, he deserves censure or exclusion.”

A spokesman for Green did not respond to a request for clarification of the congressman-elect’s claim that the CDC’s data may have been “fraudulently managed.”

Green was recently elected president of the Republican freshman class. He last year withdrew as President Trump’s nominee for Army secretary amid criticism of his past comments about Islam, evolution and LGBT issues.

Lena Sun contributed to this report.