Ocasio-Cortez, D-N.Y., made the comparison to her Instagram followers during a live stream Monday.
"The fact that concentration camps are now an institutionalized practice in the land of the free is extraordinarily disturbing," she declared.
After seeing outrage from Republicans, she doubled down on the comment via Twitter, claiming she was not engaging in "hyperbole."
"And for the shrieking Republicans who don’t know the difference: concentration camps are not the same as death camps. Concentration camps are considered by experts as 'the mass detention of civilians without trial.' And that’s exactly what this administration is doing," she wrote.
Responding in a phone interview, Collins, the top Republican on the House Judiciary Committee, said he's visited border detention centers and seen migrants treated with respect by the men and women who serve.
"It just shows either a blissful ignorance of the world and history or it shows a concerted effort of anti-Semitism and ignorance of what we do as a country," he said, criticizing top Democrats for "overlooking" such rhetoric from Ocasio-Cortez and her allies.
Starnes said either way, "it's not pretty" and Democrats have "serious problems" with some of the more left-wing members of the caucus.
Collins said House Republicans offered money for humanitarian aid a few weeks ago and it was voted down by Democrats.
"Hopefully somebody is gonna wake up and realize that this faux compassion is really not there because they've offered nothing to fix our crisis on the border," said Collins, accusing the Democrats of using migrants as political "pawns."
Ocasio-Cortez has repeatedly called for Immigrations and Customs Enforcement to be abolished, arguing in February that "Latino people are descendants of Native people" and should not be subject to U.S. immigration laws.