Former Florida Gov. Jeb Bush (R) criticized Hillary Clinton on Sunday for a “disgraceful” new ad from a liberal group that criticizes former President George W. Bush and highlights Jeb Bush’s defense of his brother.

.@HillaryClinton Your political machine’s 9/11 ad is disgraceful. As a New Yorker you know the leadership my brother provided after 9/11 — Jeb Bush (@JebBush) September 20, 2015

Bush was referring to a new ad from the liberal group Americans United for Change. Though Bush refers to the group as part of Clinton’s “political machine,” the group is not associated with her campaign. The group does share a president, Brad Woodhouse, with Correct the Record, a pro-Clinton Super PAC.

The ad titled “Safe?” highlights Jeb Bush’s comment during the CNN Republican presidential debate that his brother, George W. Bush, “kept us safe.” The Americans United for Change ad says that Bush didn’t save the U.S. from a bad economy or “an unnecessary war,” and criticized his response to Hurricane Katrina.

“It’s as if Jeb Bush believes his brother’s presidency began on September 12th, 2001. But we’re not letting Jeb rewrite history,” Brad Woodhouse, president of Americans United for Change, told the Washington Post about the ad. “It’s convenient but not honest to ignore the facts that the worst attack on American soil since Pearl Harbor happened on George W. Bush’s watch after dismissing warnings from U.S. intelligence officials weeks before 9/11 that Osama bin Laden was ‘determined to strike in US’ and that his terrorist network might hijack American planes.”

The 30-second ad will air on cable news stations this week. Details on how much Americans United for Change spent on the ad buy were not available.