Former Maryland Gov. Martin O'Malley said on Tuesday that he hopes his presidential rival, former Secretary of State Hillary Clinton, regrets invoking the attacks on Sept. 11, 2001 when explaining her ties to Wall Street.

O'Malley used some of the harshest criticism he's had for Clinton, calling the comments "disgraceful."

"I thought it was disgraceful, actually, what she said," he said Concord News Radio. "Trying to pump out a smokescreen to distract from the real issue from her alignment with the big banks of Wall Street by wrapping herself in the sentiments in the tragedy of 9/11. And hopefully she regrets the mistake and we can move on to healthier debate."

At the Democratic debate, Clinton cited the attacks while defending donations she's received from Wall Street banks.

"So, I represented New York, and I represented New York on 9/11 when we were attacked," Clinton said at the debate on Sunday. "Where were we attacked? We were attacked in downtown Manhattan where Wall Street is."

O'Malley said he thought Clinton was trying to distract people from her Wall Street friendly policies.

"I didn't understand what she was saying, I thought she was trying to distract people from the fact that she is in fact her economic theories are very much aligned with the big banks of Wall Street," said O'Malley. "Whose theory of how America's economy works is of the few, by the few, for the few.

"She's the only candidate on that stage that doesn't believe the banks have become too big to jail, too big to fail, and too big to manage — shouldn't be continually out there for us to bail out with our tax dollars," he continued. "She's the only one of them three of us that is opposed to modern version of Glass-Steagall so that we separate speculative banking from traditional banking that all of us ensure. That's not capitalism. What, you place bad bets and we have to bail you out?"