Updated 11:25 a.m. ET, 2/24/2014
(CNN) - Milton Wolf, a radiologist and GOP primary challenger against incumbent Sen. Pat Roberts of Kansas, issued a statement Sunday admitting he made "insensitive" comments about X-ray images he posted online, including an image of a person decapitated by gunfire.
"Several years ago, I made some comments about these images that were insensitive to the seriousness of what the images revealed. Soon thereafter, I removed those images and comments, again several years ago," he said in a statement.
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The story was first reported by the Topeka Capital-Journal, which got the images but did not show them to the public. The Capital-Journal's Tim Carpenter asked Wolf about the images in a tense, eight-minute video posted online alongside the article.
The candidate argued he was legally allowed to post those images online because he was not revealing the patients' identities and he was doing so for educational purposes. He also did not answer questions about whether he still posts such photos.
In his statement Sunday, Wolf put the blame on Roberts, accusing his "political adversary" for bringing the images to the public.
"However, my mistakes are my own, and I take full responsibility for them," he said.
A diagnostic radiologist, Wolf graduated from the University of Kansas and attended the University of Kansas School of Medicine. He completed his residency at the University of Missouri at Kansas City.
In the statement Sunday, Wolf said he has long published educational material on medical imaging and said he has "taken care to maintain patient privacy."
The Capital-Journal interviewed multiple medical professionals in Kansas who panned Wolf's use of the particular images referenced in the article, as they reportedly seemed to poke fun at the patients. For example, the image of the patient whose head was decapitated was posted on Facebook with Wolf describing it as "one of my all-time favorites."
"From my residency days there was a pretty active 'knife and gun club' at Truman Medical Center. What kind of gun blows somebody's head completely off? I've got to get one of those," he wrote, according to the Capital-Journal.
The newspaper describes the image as "a skull broken apart like a smashed pumpkin. Chunks of skull remain attached by tissue with vertebra exposed at the neck."
A second cousin (once removed) of President Barack Obama, Wolf paints himself as a conservative activist with the guts to stand up to the GOP establishment. As a doctor, he frequently campaigns against the Affordable Care Act and proposes his own plan that he calls "PatientCare."
In the article, Leroy Towns, a spokesman for Roberts, said the postings raise questions about Wolf's responsibilities to maintain privacy of patient medical information as well as questions about his viability as a candidate.
"For any doctor to make patient records public and then use the records for public discussion and entertainment is just unthinkable," Towns told the Capital-Journal. "Allegations of such lack of judgment demand extensive scrutiny and investigation."
Wolf said Roberts' response was "character assassination."
"Pat Roberts has not been able to identify a single issue on which he thinks I am wrong and so he's doing things the Washington way: character assassination," Wolf said in the statement. "Kansans should know that I will not be intimidated by their bullying."