Seven people are known to have perished throughout the insurrection and in its immediate aftermath.
Three more were police officers; one died after an altercation with demonstrators, and two more committing suicide in the days and weeks after the riot.
Glenn Greenwald, a freelance journalist, tweeted in response to Ocasio-Cortez's Sunday announcement: "Claiming that there is "almost 10 dead" from the 1/6 riot is deceitful in the extreme."
"Four people died on 1/6: all Trump supporters."
"It's possible to connect a couple of the later police suicides to 1/6 if one stretches enough but this need to exaggerate 1/6 speaks for itself."
He continued: "The lesson of 9/11 is - or should have been - that allowing politicians to deceitfully exaggerate domestic threats or exploit the propagandistic term "terrorism" to justify civil liberties assaults is dangerous in the extreme."
"Clearly, many have forgotten this lesson."
The four Trump followers included Ashli Babbitt, 35, an Air Force veteran from Southern California, shot and killed by a Capitol Police officer as she climbed through a broken window heading to the Speaker's Lobby inside the Capitol.
Rosanne Boyland, 34, of Kennesaw, Georgia, was trampled to death. Benjamin Philips, 50, the founder of a pro-Trump website called Trumparoo, died of a stroke while in Washington DC, while Kevin Greeson, 55, of Athens, Alabama, had a heart attack during the riot.
The three officers included Brian Sicknick, 42, who attempted to repel the demonstrators, then returned to his division office and collapsed. Investigators think he may have been killed as a result of a reaction to bear spray or mace.
Jeffrey Smith, 35, was hit on the head with a metal pole and sunk into a deep depression after the protest, and shot himself on the way to work on January 15.
Howard Liebengood, 51, died by suicide on January 9.
Ocasio-Cortez was reacting to a report in Rolling Stone magazine, published on Sunday, that announced that Congressional staff members met regularly with the rioters before the insurrection.
The two sources for the Rolling Stone piece said seven Republican members of Congress either participated in the work or sent top staffers; Marjorie Taylor Greene, Paul Gosar, Lauren Boebert, Mo Brooks, Madison Cawthorn, Andy Biggs, and Louie Gohmert.