Republicans attack Clinton over 'secret' email information

Republicans quickly pounced on Hillary Clinton Friday after it was revealed that some emails on her private server would not be released because they contain information deemed "top secret."

Donald Trump called the email declaration "a disaster" for Clinton. Marco Rubio called it "unacceptable" and said, "this is a disqualifier."

Jeb Bush said on Twitter: "We need a president who can keep our secrets secret. Obviously that's not Hillary Clinton."

Related: State Department Declares Some Hillary Clinton Emails 'Top Secret'

The State Department on Friday denied the release of 22 emails because of "top secret" information. The 22 documents are in seven email chains, the department said.

The emails were not marked classified at the time they were sent, but were "were upgraded at the request of the intelligence community," State Department spokesman John Kirby said.

Clinton has repeatedly said that she did not send or receive any emails marked as classified at that time.

The new top secret designation forced Clinton's campaign to once again address the use of private email just days before the important Iowa caucuses.

Clinton's campaign said in a statement that Clinton wants the emails released. Her campaign spokesman objected to the newly classified material as "over-classification run amok."

Chris Christie used the new email scrutiny to attack Clinton's credibility in Iowa, days ahead of the caucus.

"Didn't she look us in the eyes and tell us there was not a bit of classified information on her person server?" Chris Christie said at a campaign event Friday. "She has now definitively — without any question — lied to us."

Bernie Sanders, engaged in a neck-and-next struggle with Clinton for Iowa's voters, didn't address the issue at all, except to repeat his stance that there are other matters more worthy of discussion.

"There is a legal process in place which should proceed and not be politicized," Sanders said in a statement Friday. "The voters of Iowa and this nation deserve a serious discussion of the issues facing them."

Related: AOL interview with Hillary Clinton -- behind the scenes.

More from NBC News
The lid: What latest Clinton email news means for Dem primary
Cruz turns his crosshairs on Rubio in final hours
Seeking opportunity, Sanders intensifies jabs at Clinton